Mark Strauss does an excellent job describing and assessing the so-called “criteria of authenticity” used to evaluate the sayings of Jesus (Four Portraits, 359-62). I have expanded this list a bit using volume 1 of John Meier’s The Marginal Jew. The use of criteria for determining the authenticity of Jesus’ sayings are part of an inductive argument which can only lead to the likelihood that a given saying goes back to Jesus. If multiple criterion imply that a saying is authentic, that increases confidence in that saying.
- Dissimilarity (Discontinuity in Meier, 1: 171-174, also known as originality, or dual irreducibility). If a saying is unlike anything found in Judaism or the early church, then it is more likely to be correct. But there is a serious problem here: How can a historical Jesus be divorced from Judaism, the religion of the Hebrew Bible and the first century Palestine in which he ministered? Why Jesus reflect a culture different from Judaism if he was a Jew?
- Multiple Attestation. This assumes at least a two source hypothesis, If a saying is in Mark and Q, then it is more likely to be authentic. If a saying appears in Mark, Q, and Gospel of Thomas, etc, this “triple attestation” that is more likely to be original. On the surface, this seems reasonable although it assumes several things about source criticism. However, it is not applied consistently by some scholars. For example, Mark 10:45 appears in multiple layers of tradition (as defined by the Jesus Seminar), et the saying is dismissed as a creation of the church.
- Coherence (Meier, 1:176-177, also known as conformity, or consistency). The criterion of coherence states that whatever statements of Jesus that are supported generally by the other criteria are more likely to be authentic. This assumes that one has been able to isolate some authentic material using the other criteria and have established a database for dealing with other sayings. This is not unlike the Jewish method of judging a prophet – the Torah was the database by which prophetic books were evaluated. If they contradicted the Torah, they could not be authentic.
- Embarrassment (Meier, Marginal Jew 1:168-171, also known as contradiction). The pericope is not the sort of thing that the early church would have gone out of their way to create. If one were imagining a community of believers creating stories about Jesus, it follows that they would suppress stories that were embarrassing or difficult to fit into the developing Christology of the church. Meier uses the example of the baptism. Jesus (the sinless son of God) presents himself to John the Baptist, a sinful mortal, in order to be baptized, even though John’s baptism was announced as for repentance and the forgiveness of sins. Mark 1:4-11 has Jesus simply presenting himself for baptism, Matthew 3:13-17 has Jesus explain to John why baptism is necessary, Luke 3:19-22 places the arrest of John before the baptism story (as a flashback) so that the reader does not immediately connect John with the actual baptism. By the time John writes, there is no actual baptism, only the witness of the Spirit to the identity of Jesus.
- Rejection and Execution (Meier, 1:177). This element is quite different than the others. It assumes that Jesus was in fact arrested by the Jews and tried for something, and executed by the Romans. What might he have taught and done that would have led to that level of punishment? If he was a teacher of parables and short witty aphorisms, then he is unlikely to get himself crucified.
- Semitic Flavor. Strauss includes although it was not really one of the Jesus Seminar’s original criteria. If a saying or action of Jesus has a “pronounced Jewish or Palestinian flavor, it is more likely to be authentic” (361). His example is the use of the Aramaic word abba in Mark 14:36. The assumption is that Jesus spoke as a Palestinian Jew and (presumably) later writers would be unfamiliar with a Semitic context. This criterion may not be helpful if the writer is Jewish; Matthew could create Jewish things for Jesus to say, for example.
- Divergent Traditions. Occasionally authors preserve traditions which do not serve their purposes. In Matt 10:5-6 Jesus tells his disciples to not go to the Gentiles, yet in Matt 28:16-20 he tells them to go to all the nations. As Strauss points out, this criterion is difficult to use since we may not understand the purpose of the Gospel writer. In the example given, it is possible the situation during Jesus’ ministry was different than after the resurrection.
In the end, do these tests achieve anything? It has become standard among conservative to state that the use of the Criteria tells us very little about Jesus and then dismiss them out of hand. But I like how Blomberg concludes his discussion of the criteria: these arguments build on faith evidence with does actually exist (Jesus and the Gospels, 221).
I would unpack this statement in two directions. If one already has faith that the Gospels accurately record Jesus’ words, then the criteria of authenticity provide evidence in favor of that faith. We can be assured that we have accurate accounts of the sorts of things Jesus actually said. On the other hand, if one assumes Jesus did not say certain things (Son of Man, eschatology, etc.), then the criteria will prove that assumption, Jesus could not have said the things the Gospels claim.
In the end, these tests are still matters of faith, and pretending that they are objective is a sham.