After the resurrection, Jesus gives many “convincing proofs” of the resurrection (1:3). The word Luke selects for “proof” (τεκμήριον) in this opening paragraph is word associated with other historical texts in the ancient world. The word is different than witness (a key word in Luke’s introduction to Acts) since “proof” refers to “evidential proof credible on its own merits” (EDNT, 340). Keener says the phrase “many proofs” appears in Hellenistic historiography (1:666). The Greek historian Thucydides, for example, makes a statement the offers proof for the assertion using this word (2.39), and he used the verb in his introduction of his history with the sense of “prove positively” (1.3). I am not sure Luke would have intended this word to be understood in the same sense as Aristotle, who used the word in contrast to fallible signs (σημεῖον). For Aristotle, the word refers to “demonstrative proof” (LSJ).
Another way of understanding of the word is as a “confirming sign.” When Josephus created a speech for Joshua just before the Israelites enter the Promised Land, he described the miracles Israel experienced in the wilderness as “many signs” (Ant. 5.39 διὰ πολλῶν τεκμηρίων). This is intriguing; perhaps Luke refers to Jesus doing things to prove he was actually alive (eating with the disciples, Luke 24:41-43) or miracles (John 21:4-8). The “signs” were proof Jesus was indeed alive.
Most likely the “evidence” Jesus gave was scriptural proof drawn from the Hebrew Bible. Jesus explained to the disciples the key texts about the messiah and demonstrated to them Scripture anticipated a suffering messiah who would die and rise again. Certainly the disciples needed to be convinced Jesus had really died and was not alive (John 20, Thomas), the bulk of the proof took the form of opening the disciples minds to the idea that messiah came to suffer and die before judging and ruling the nations. This is exactly how Luke ended his gospel, the disciples who met Jesus on the road to Emmaus: “and beginning with Moses and all the Prophets, he interpreted to them in all the Scriptures the things concerning himself” (Luke 24:27).
Why would Jesus need to provide “convincing proofs”? In Second Temple Period Judaism, no one expected the messiah would die, let alone rise from the dead. A possible exception is 4 Ezra, but even in this book the messiah establishes a kingdom and dies after a very long reign. There was no Jewish expectation the suffering servant of Isaiah 40-55 would die, and no one read that text as messianic quite the way Christians do.
Jesus gives these proofs or signs to draw his disciples to the conclusion the messiah had to die and be raised from the dead. This claim demands a decision from disciples but also the reader of Acts. If Jesus was who he claimed, then what is going to happen at Pentecost?
When we read Peter’s sermons in Acts 2-3, there are several passages from the Hebrew Bible which could qualify as “convincing proofs.” What does Peter claim about Jesus in these sermons?