The answer is of course yes. Now find out the historical evidence. If you have a son or daughter or a co-worker or husband who challenges you, send him or her to this link.
Can you have an effect without a cause?
In the last article, Archaeology and John’s Gospel, I asked whether skepticism chic is passé. Maybe I should have used the term hyper–skepticism. Is it waning? No.
Did Jesus even live? Personally, I have no doubt that he did. But we should take a moment to provide resources that counter hyper-skepticism.
When you throw a rock into a still pond, ripples radiate outward. The rock is the cause, and the ripples are the effect, to keep things simple.
Let’s apply the rock-into-the-pond image. Jesus is the Rock. His disciples and his movement and the written Gospels are the ripples. His “splashdown” in his home country Israel caused or produced ripples that went around the Mediterranean world. They are still going strong throughout the world today.
In Part Four here in a long series, we’re supposed to be talking about the historical reliability of the Gospels. But those title questions take us into the realm of hyper-skepticism and far away from the commonsense world of time and space and history that we are used to.
To counter the nonsense about the non-existence of the historical Jesus, it is customary to analyze what non-Christian sources say about him. I will do this, up to a point. I mention only passages that the vast majority of scholars rarely doubt. In the References and Further Reading section, I provide links to books and websites that discuss more than these passages mentioned here. Finally, this article returns to the main purpose of the series, mentioning other persons who appear both inside the Gospels and in texts other than the Gospels, non-Christian sources, in other words.
Hovering over the references below will bring up the NET Bible version on each of these.
1. Where do questions like those in the title come from?
The larger context of hyper-skepticism: René Descartes (1596-1650) sat alone in a room and conducted an experiment, of sorts. He wondered how far he could get if he were to doubt everything – and I mean everything: his five senses; the existence of his own body; the truths of mathematics and science; God’s existence; whether Descartes was awake or asleep, dreaming; and whether a malicious deity were deceiving him.
What did he come out with? He is a thing that thinks. “I think, therefore I am.” Even when he doubts, his mind exists. Even if he lives in a dream, then his mind exists. Even if he is deceived by a malicious deity, then there is a mind that can be deceived. He can even be a disembodied thinking thing. To his credit, however, he tried to rebuild secure knowledge in the rest of hisMediations, but today’s philosophers conclude that he was naïve in his rebuilding project. He let the hyper-skeptical genie out of the bottle.
Descartes is considered the founding father of modern philosophy, and the hyper-doubt goes on today.
So, to ask whether an historical figure like Jesus even existed is child’s play for the hyper-skeptics, if they can doubt basic and commonsense truths right in front of their faces, before their eyes.
At the end of this article, see a series on postmodernism, which further analyzes the origins of hyper-skepticism, among other things.
2. So what do these non-Christian sources say about Jesus?
They are numbered for clarity.
(1) Josephus (c. AD 37 to post-100), a Jewish historian, records some interesting comments about Jesus and James, the half-brother of Jesus. We quote from his book Jewish Antiquities, his second major work (Jewish Wars is the first), written in the early 90s.
The first passage has sparked controversy because it is widely believed that a Christian scribe interpolated (inserted) some clauses. But here is an expurgated version:
Around this time lived Jesus, a wise man. For he was a worker of amazing deeds and was a teacher of people who gladly accept the truth. He won over both many Jews and many Greeks. Pilate, when he heard him accused by the leading men among us, condemned him to the cross, [but] those who have first loved him did not cease [doing so]. To this day the tribe of Christians named after him has not disappeared. (from Jewish Antiquities 18.3.2; quoted in Van Voorst; readers may read the fuller version here, scrolling down to Chapter 3)
Scholars agree that Josephus wrote a passage on Jesus. Most scholars would agree on this restored version. When they don’t agree, they usually make Josephus a little more hostile (Bruce, p. 39).
This excerpt corroborates some elements in the Gospels. Specifically, Jesus was a wise man, though the Gospels do not use that description in those exact terms. He worked amazing deeds. He was a teacher. He won over many Jews. Leading men accused him. Pilate had him crucified. His followers did not cease loving him. They continue up to the time of Josephus, who was writing in Rome, where a Christian community flourished. As for the observation that Jesus won over many Greeks or Gentiles, Josephus was simply retrofitting his present day with the ministry of Jesus, for the Gospels say Jesus’ outreach to Greeks or Gentiles was minimal.
But one thing is certain: Josephus does not doubt that Jesus existed. Van Voorst writes: “[the excerpt] . . . affirms the existence of Jesus. If any Jewish writer were ever in a position to know about the non-existence of Jesus, it would have been Josephus. His implicit affirmation of the existence of Jesus has been, and still is, the most significant obstacle for those who argue that extra-biblical evidence is not probative on this point” (p. 99).
Josephus was a careful enough historian to have noted whether the Jesus movement had been built on a fraud, on a zero, on a nothing, on the complete absence of a real person. Josephus could have written: “The followers of this non-existent Jesus say he existed, but no one ever saw or heard him.” But Josephus didn’t write that.
(2) Next, Josephus recounts the execution of James, the half-brother of Jesus. Josephus intends Ananus the high priest in Jerusalem to appear bad because the Romans replaced him. Since Ananus behaved rashly, the Romans were justified in their policy.
[Ananus the high priest] assembled the sanhedrin of judges, and brought before them the brother of Jesus, who was called Christ, whose name was James, and some others, [or, some of his companions]; and when he had formed an accusation against them as breakers of the law, he delivered them to be stoned. (SeeJewish Antiquities 20.9.1; scroll down to Chapter 9)
The majority of scholars agree that this passage is authentic, without interpolations. Josephus recognized that James the (half) brother of Jesus was an important leader of a new religious movement (earliest Christianity) in Jerusalem, important enough for Josephus to recall his name and execution. His passage indeed corroborates the Gospels because some verses mention James as the Lord’s (half) brother (Matt. 13:55 // Mark 6:3).
(3) Tacitus (c. 56-120) was considered one of the most careful of Roman historians. He makes a passing reference to Jesus in the context of Nero blaming Christians for the fire in Rome, a fire that began on July 19, AD 64. He wanted to deflect blame from himself. The following portion of his Annals was written about AD 112.
Tacitus writes with a clear note of contempt:
But neither human resources, nor imperial munificence, nor appeasement of the gods, eliminated sinister suspicions that the fire had been instigated. To suppress this rumor, Nero fabricated scapegoats – and punished with every refinement the notoriously depraved Christians (as they were popularly called). The originator, Christ, had been executed in Tiberius’ reign by the governor of Judaea, Pontius Pilatus. But in spite of this temporary setback the deadly superstition had broken out afresh, not only in Judaea (where the mischief had started) but even in Rome. All degraded and shameful practices collect and flourish in the capital (Annals 15.44.2-3; trans. by Michael Grant, The Annals of Imperial Rome, Rev. ed. Penguin Classics, 1977, p. 365; online)
The rest of the passage in Tacitus describes the torture that the Christians suffered. They were covered in animal skins and torn to pieces by wild dogs; they were crucified; or they were turned into human torches, in Nero’s gardens, though there seems to be a textual problem with the “torches” (Van Voorst, p. 42. note 59).
Tacitus corroborates the Gospels on the following points: Christ was the originator of the religion (“deadly superstition”); he was executed during the reign of the Roman Emperor Tiberius (ruled AD 14-37); he was executed by Pontius Pilate (ruled in Judea AD 27-37); there was indeed a temporary setback after Christ’s death, as the Gospels indicate; but the religion flamed back up. It made it to Rome (Christ predicted that it would go into all the world in Matt. 24:14; 28:16-20; Mark 13:10). Tacitus mentions Judea as the place of origin. This probably reflects the fact that Christianity was centered there after the death of Jesus.
3. Were Josephus and Tacitus eyewitnesses to Jesus?
No. But they were careful historians – at least careful enough to affirm that Jesus existed and was crucified under Pontius Pilate. Eddy and Rhodes explain why Tacitus himself would look into the existence of Jesus, and not depend on Christian hearsay, but possibly on official records (pp. 182-84). J. P. Holding has an excellent online article on Tacitus (“Nero’s Scapegoats”). Hyper-skeptics must work their way through key books and articles in the References and Further Readings section, below.
4. What about other New Testament figures in non-Christian sources?
This article is really about the historical reliability of the Gospels, not just the bare existence of Jesus, corroborated by non-Christian sources. Again, these references are numbered for clarity.
(1) There is another important person who appears in all four Gospels and Josephus: John the Baptist. The lengthy account in Josephus’ history and the four Gospels agree on some main points. John is called the Baptist; he was a good man who commanded the Jews to exercise virtue, in righteousness to man and to God, and in piety; John commanded them to come to baptism in water; crowds came to him, for they were moved to hear him. Herod the tetrarch made him a prisoner and put him to death (read the account here).
The differences in Josephus and the Gospels are mainly political. Herod kills John because the ruler feared John’s influence over the people, for he might raise a rebellion against Herod. But the Gospels say that Herod executed John because Herod feared John and because John condemned the ruler for marrying his brother Philip’s wife, Herodias (Josephus alludes to these things, too). Both can be true. Herod feared John’s influence and was angry at his denunciation.
Since the excerpt on John the Baptist is long, I won’t quote it here. Readers are invited to go to Jewish Antiquities 18.5 (scroll down to Chapter Five).
(2) Josephus mentions Annas and Caiaphas the high priests during the ministry of Jesus or close to his timeframe (Jewish Antiquities 18 and 20; do a control-F search on their names or Ananus). The Gospels also mention them: Annas (Luke 3:2; John 18:13, 24; cf. Acts 4:6) and Caiaphas (Matt. 26:3, 57; Luke 3:2; John 11:49; 18:13, 14, 24, 28; cf. Acts 4:6).
(3) Finally, as noted, Josephus discusses Pontius Pilate in several places (Jewish Antiquities 18 and Jewish Wars 2; do a control-F search on Pilate). He is referenced about fifty-eight times in the four Gospels (many in parallel passages), three times in Acts, and once in 1 Timothy 6:13.
We could do a study of these persons, both in the Gospels and Josephus. But we do not have the space (see Evans, pp. 166-75, for a good study on Pilate; Evans explains the differences between Pilate in Josephus and the Gospels). Suffice it to say here that Josephus does not doubt the existence of John the Baptist, Pontius Pilate, and the two high priests. So why should we? The Gospels and outside written sources cohere together often. Even if they do not cohere with perfect precision, I still see no reason or need for hyper-skepticism about the existence of Jesus and of others mentioned inside the New Testament and in texts outside the New Testament (see Q & A Nine).
5. Are there more non-Christian sources?
Yes, and I provide links to online articles and books that discuss those sources (see especially J. P. Holding, References and Further Reading, below). But perhaps the question is – why are the unambiguous and solid sources so few? Also, why are there not more unimpeachable sources that are contemporary with Jesus? These questions can be answered in seven ways.
First, Roman histories that were contemporary with Jesus or nearly so have perished. Second, the ancients did not live in the world of satellite hookups. So there was a time lag between the events and writing them down. Third, earliest Christianity was not on Rome’s radar screen, so to speak, until the religion was perceived to be a threat or at least interacted strongly with life in Rome. Thus, when Jesus was perceived to be a threat in small, outlying regions called Galilee and Judea, he was executed by the Roman authorities stationed in Jerusalem. End of story, for elite Romans living in the largest city in the Mediterranean world – Rome. By analogy, Pontius Pilate is such a minor figure that he is nowhere mentioned in the Roman histories, except when they bring up Jesus, specifically only in Tacitus (see Q & A Two, above).
Fourth, Roman historians, in treating of religions, do not delve into their origins in any detail. The historians cared only about the religions now, and how they may influence Roman society. For example, Tacitus does not explore the origins of Judaism, not even Abraham, Moses, or David, but Tacitus does examine the Judaism of his day. Fifth, the first full Gospels were not written and shared among communities until about AD 70 and later. So it should not be expected that the Gospels would come into the hands of first-century historians. Rather, it is the second-century historians who take Christianity seriously, as it spread around the empire. And the historians still did not have access to the written Gospels, in all likelihood – in the age before printing presses, after all.
Sixth, a less-than-observant reading of the Gospels may give the impression that Jesus’ ministry impacted the whole known world right after a miracle happened, beamed live by satellite into ancient Gaul (modern France). It is true that his ministry impacted Israel, particularly Galilee, but it did not yet spread much beyond his homeland and its capital, Jerusalem. Roman historians probably would not have heard of him. Seventh and finally, if elite Roman historians had heard of him, there is no reason to expect that they would have written about him. During his ministry, many self-proclaimed prophets and self-styled messiahs wandered around the ancient world. From a comfortable Roman’s point of view, Jesus would have been one voice among many.
To repeat, Roman historians took notice of the Jesus movement-turned-church, only when it came across their “radar screen” several decades after he was resurrected. By then he was not on earth to be interrogated.
Personally, I’m surprised that the historians and other authors refer to Jesus specifically as often as they do, and accurately, too, in the main. These seven explanations fit the logic of history in the ancient Roman world, at least to me they do.
See Van Voorst, pp. 70-71, and Eddy and Rhodes, p. 168.
6. Do the Gospels count as historically reliable testimony?
Yes, and that’s what the entire series endeavors to establish. I see no reason to accept, a priori, the notion that when a Gospel disagrees on a detail with a non-Christian text, the Gospel is automatically wrong.
In any case, the series is really about the historical reliability of the Gospels, without entering the world of hyper-skepticism to prove that Jesus existed. He enjoys the support of historically reliable Christian and non-Christian sources. For me, that’s enough.
7. But weren’t the Gospels written by partisans, so the texts cannot be trusted?
I like how one scholar frames the answer. Craig Evans writes: . . . “if Jesus really said little of lasting significance and was unable to train his disciples to remember accurately what little he did say, then we must really wonder why the Christian movement emerged at all” (p. 47).
For our purposes, this quotation means that you cannot have an effect or result without a cause. So even though the Gospels were written by authors with a strong point of view, that does not imply that Jesus never lived. Many Greek and Roman authors who intended to write faithful or even fanciful accounts of an actual person also wrote from a strong viewpoint. See these texts about Socrates, not written by him: Apology (Defense) by Plato; Clouds by Aristophanes; and Memorabilia and Apology by Xenophon. Some texts are more accurate than others. But does that mean we should doubt Socrates’ existence, at a bare minimum? Of course not. And so the Gospels fit into their larger literary context.
Today if an extra-cautious rationalist does not believe in the Gospel miracles or believes that the Gospels are built on a legend, then he outwits himself by half if he denies the mere existence of the historical Jesus. Inaccurate and accurate accounts were built up around Socrates, but he still existed, in history (see Q & A Nine).
Mark D. Roberts assesses all four Gospels in a reasonable way. They are “Truthful History Motivated by Theology” (Can We Trust the Gospels? Crossway, 2007, p. 121).
8. How does all of this relate to the Gnostic texts?
Some scholars look for passages in the Gnostic and apocryphal texts, particularly in the Gnostic Gospel of Thomas, to find out whether they may be early and independent sources for the existence of the historical Jesus. These scholars believe that they may have found some passages. But their goal is the same as my cause-and-effect comment, below, in Q & A Ten. They believe that a few parts of the Gnostic texts did not emerge in a vacuum, but have a real, historical Jesus standing behind them, if only remotely. However, on the whole, the Gnostic and apocryphal texts are clearly derivative or stray far from the historical Jesus.
Readers may see the References and Further Reading section for more information, looking especially for Bruce, Van Voorst, and France.
9. So should we doubt the existence of Jesus, as hyper-skepticism says, or not?
Not. Hyper-skepticism demands too much of me. It requires me to believe that the apostolic community perpetrated a hoax on society. All of the earliest disciples conspired together to create a religious movement from a fraud – a massive prank. They supposedly engineered Christ’s crucifixion and resurrection. The disciples supposedly did this even though they never gained any riches or lived a comfortable life. Hyper-skepticism requires me to believe that the written Gospels are based on an absence or a zero. Hyper-skepticism requires me to believe that the Jesus movement spread like wildfire because of a nothing, a non-existent person.
Maybe it is widely (and inaccurately) believed that Christianity rose to power without any trouble, from the first day, so it was the Christians who harassed people with torture and prison, including martyrdom. Just the opposite. The early Christians were the hunted and the persecuted and the martyred, just as we saw in Tacitus. It is one thing to die or suffer presecution for something that you believe is true (though it really isn’t). But it is quite another to die or suffer presecution for a belief that you know is false. The members of the Jim Jones cult drank poison because they believed in their leader, not because they followed a messiah they knew to be false. Maybe a few really extreme and deluded lunatics would die or suffer persecution for a belief that they know to be false, but surely not a huge number, spread out over the Roman Empire. It seems that at least a few of the earliest disciples, suffering from persecution and martyrdom, would reveal to the authorities that the whole Jesus movement is a fraud and he never existed at all. However, the disciples did not do this, and they do not fit the profile of deluded lunatics. Rather, they were honest, rational, and coherent, intellectually.
It is difficult to imagine that the disciples really believed and professed absurdities like these, if only among themselves: “We follow a non-existent person who never spoke and never did any miracles! We never saw him! We are a mushroom cult that hallucinates! We suffer from large-scale delusions! This complete non-human / human zero is why we never suffer persecution and martyrdom! We manufacture those reports about our persecution and martyrdom! We’re actually getting rich and living in mansions! Thank you, non-existent Jesus! Now let’s go out there and deceive people! Can I get a witness?” “No,” should come the wise reply.
Delusion is not a “psychological miracle.”
10. What does your cause-and-effect title mean?
In the world we live in, up here above quantum fluctuations, we cannot have an effect without a cause. We cannot get something out of nothing. As noted in the Introduction to this article, when you throw a rock into a still pond, ripples go outward in concentric circles. To put things simply, Jesus of Nazareth is the cause. He is the Rock. At a minimum, the apostolic community and the written Gospels are the effect. They are the ripples that go outward from Israel and into all of their known world.
Therefore, it is more plausible to believe that the historical Jesus existed than to believe that he did not. He is the one who got the whole movement started.
And at a maximum, it is still going around the world, just as Jesus predicted and commanded (Matt. 24:14; 28:16-20; Mark 13:10). I expect that it will continue to flourish and grow. The ripples can get stronger, not weaker, today.
11. So what’s the bottom line on all of this?
Much – not all – of this article got sidetracked into the nonsense about the non-existence of Jesus and away from the main goal of the series: the historical reliability of the Gospels. For me, in this specific article, it is remarkable how many times the Gospels enjoy corroboration from Greek and Roman and Jewish sources: Jesus; James his (half) brother; John the Baptist; Pontius Pilate; Ananas and Caiaphas; many Herods (the Great and his offspring and their wives or husbands); the Pharisees and Sadducees; and, to step outside the Gospels, Gamaliel in the Mishnah, Paul’s teacher (cf. Acts 5:34, 22:3), and others. The corroboration could be extended into non-Christian sources not discussed in this article (see below for links, particularly J. P. Holding).
The Gospels reflect their historical context. They may go in directions that are not strictly sequential with the events in Jesus’ life, taking instead a thematic or theological direction. But the Gospels are still rooted in history — in the life-story of a real person who lived in Israel, about four decades before the destruction of the temple in AD 70, by the Roman General Titus (in that link see an image on the Arch of Titus, of the Menorah and more, triumphantly being carried through Rome).
The evidence in the series is mounting: the Gospels are trustworthy on an historical level.
12. What does all of this mean in the big picture?
Hyper-skeptics seem to believe that if they can trash Christianity and somehow spark a mass defection, then all the world will be better off. But apparently they do not realize that a competitor religion has entered the marketplace of ideas, with some force (pun intended). When people defect from Christianity, they may not turn secular. They may join a religion (can you guess which one I’m hinting at?) that denies basic freedom of expression and thought – the very freedom that the hyper-skeptics depend on to attempt to eviscerate Christianity. But if this competitor religion were to win the day, its leaders will not permit the hyper-skeptics to attack its holy book and its founder. Imprisonment or death may be imposed on the hyper-doubters and scoffers.
Sometimes I sit back to figure out why people make outlandish claims – about history (no need to talk about miracles now). But I cannot figure out why hyper-skeptics overreach and wish to tear down a religion that harms no one today with a holy war or death by stoning for adultery (usually adulteresses), for example. I have read the personal stories of some hyper-skeptics, and they indicate that in their youth they got burned by a church. I concede that too often, sadly, the meanest people are in church, but a lot of normal people have unpleasant personal experiences with a religion; yet they leave things alone without saying that Jesus never existed.
Anyway, for further reflection . . .
13. So what does all of this mean to the Church of all denominations?
It is doubtful whether you will come in contact with a hyper-skeptic. If so, you may use the resources, below, in the References and Further Reading section. Maybe this article will help, too. I suggest that you give very little time to true-blue hyper-skeptics. They will never be satisfied. If there are three high-quality references to Jesus and many references to other New Testament figures outside the Gospels, then the hyper-skeptics will clamor for more, always more.
But if I may counsel you members of the Church wherever it is found – in the unlikely event that you were to meet a hardcore hyper-skeptic who tells you that Jesus may not have existed, you tell him that the four Gospels are reliable enough for you. Writings other than the Gospels corroborate again and again the existence of persons – not only Jesus – inside the Gospels. All of the sources cohere together and correspond to each other. Jesus existed, and so did a lot of other New Testament figures. Not even a hyper-skeptic can have an effect without a cause. Jesus is the cause, and his religious movement – even today – is the effect. The ripples are still going strong.
The hyper-skeptics overreach. If I may counsel them for a moment, they should acknowledge that Jesus of Nazareth lived. They can then move on to attack the content of the Gospels themselves, like the miracles. (That’s irony, folks!)
Articles in the Series
- New Testament Manuscripts: Preliminary Questions and Answers
- Basic Facts on Producing New Testament Manuscripts
- Discovering and Classifying New Testament Manuscripts
- The Manuscripts Tell the Story: The New Testament Is Reliable
- Church Fathers and Matthew’s Gospel
- Church Fathers and Mark’s Gospel
- Church Fathers and Luke’s Gospel
- Church Fathers and John’s Gospel
References and Further Reading
An asterisk indicates that the entry should be read or purchased first.
* Paul Barnett. Is the New Testament Reliable? 2nd ed. Intervarsity, 2003. Pp. 22-34. For beginners. Go for this one and Roberts’ first.
Darrell Bock. “Extra-Biblical Evidence for Jesus: Signs of His Presence from Outside Scripture.” Bible.org. A list of (mostly) non-Christian sources, but no analysis.
* F. F. Bruce. Jesus and Christian Origins Outside the New Testament. Hodder and Stoughton, 1974. An old standard from a first-rate scholar, and he seems to have the laity in mind, but start with Barnett and Roberts.
Paul Rhodes Eddy and Gregory A. Boyd. The Jesus Legend: A Case for the Historical Reliability of the Synoptic Jesus Traditions. Baker Academic, 2007. Pp. 165-200. This is excellent, but it is for the advanced; again, start with Barnett and Roberts.
—. Lord or Legend: Wrestling with the Jesus Dilemma. Baker, 2007. Their smaller book here is designed for the laity, but it can still get technical for the true beginner. But definitely get it.
* Craig A. Evans. Fabricating Jesus: How Modern Scholars Distort the Gospels. Intervarsity, 2006. Pp. 158-79. Excellent on Josephus. For the laity, but it can get technical for the true beginner.
—. “Jesus in Non-Christian Sources.” In Studying the Historical Jesus. Eds. B. Chilton and C. Evans. Brill, 1994). Pp. 443-78. He provides a classification of the Greco-Roman and Jewish sources: Dubious Sources, Sources of Minimal Value, and Important Sources.
Louis H. Feldman. “The Testimonium Flavianum: the State of the Question.” In B. Chilton and C. Evans. Studying the Historical Jesus. Brill, 1994. Pp. 179-99. Feldman is currently the “dean” of Josephus studies.
* Richard T. France. The Evidence for Jesus. Regent College, 1986 (reprinted 2006). He respects the Gospels but does not whitewash the difficulties. Get this book, along with Bruce’s and Van Voorst’s, but after Barnett’s and Robert’s.
Gary R. Habermas. The Historical Jesus: Ancient Evidence for the Life of Christ. College Press, 1996 (1999). Written from a very conservative viewpoint. For the mid to advanced.
Murray J. Harris. “References to Jesus in Early Classical Authors.” In Gospel Perspectives: The Jesus Tradition Outside the Gospels. Vol. 5. Ed. David Wenham. Wipf and Stock, 2004 (1984). Pp. 343-68. Scholarly, for the advanced.
* J. P. Holding. “Shattering the Christ-Myth.” Tektonics.org. This article at an apologetics website has a good discussion and links to other articles on Greek and Roman and Jewish writings; the articles are well researched. But I cannot vouch for the rest of his website, though it seems well worth exploring.
* —. “Nero’s Scapegoats.” Tektonics.org. Good article on Tacitus.
* J. Ed Komoszewski, M. James Sawyer, and Daniel B. Wallace. Reinventing Jesus: How Contemporary Skeptics Miss the Real Jesus and Mislead Popular Culture. Kregel, 2006. Written from a conservative point of view, for the laity.
* Mark D. Roberts. Can We Trust the Gospels? Crossway, 2007. Pp. 139-50. Start here and Barnett.
* —-. “Do Historical Sources from the Era of the Gospels Support Their Reliability?” October 2005. He quotes a few more sources than I do in this article.
Graham H. Twelftree. “Jesus in Jewish Traditions.” In Gospel Perspectives: The Jesus Tradition Outside the Gospels. Vol. 5. Ed. David Wenham. Wipf and Stock, 2004 (1984). Pp. 289-342. Scholarly, for the advanced.
* Robert E. Van Voorst. Jesus Outside the New Testament: An Introduction to the Ancient Evidence. Eerdmans, 2000. This is the best treatment. If you are inexperienced in these issues, look into Barnett and Roberts first; then get this one.
Edwin M. Yamauchi. “Jesus Outside the New Testament: What Is the Evidence?” In Jesus under Fire: Modern Scholarship Reinvents the Historical Jesus. Eds. Michael J. Wilkins and J. P. Moreland. Intervarsity, 1995. Pp. 207-30. Scholarly, for the advanced.
Craig A. Evans thought of the rock-in-the-pond image first.