From Acts of the Apostles, by William S. Kurz, SJ, commenting on Acts 2:14, 22-33
Psalm 16 expresses Jesus’ confident hope even during his passion that he would be raised from the dead: “My flesh, too, will dwell in hope.” The reason for his hope follows: “because you will not abandon my soul to the netherworld, nor will you suffer your holy one to see corruption.” The Jewish view was that physical decay began on the fourth day after death, as illustrated in Martha’s comment that there would be an odor because Lazarus had been dead four days (John 11:39). But Jesus was raised on the third day—a sign that this prophecy that God’s holy one “would not see corruption” was fulfilled in him!
The psalm continues, “You will fill me with joy in your presence.” As Peter points out, Ps 16 cannot apply to David himself, because his tomb is in our midst to this day. This is in sharp contrast to Jesus’ tomb, which was known to be empty (Luke 24:1–8). David’s prophecy in Ps 16:10 quoted by Peter, “You will not abandon my soul to the netherworld,” could not have applied to himself since he had been dead and buried for a thousand years. But because David was a prophet and knew that God had sworn an oath to him that he would set one of his descendants upon his throne (see Ps 132:11–12), he spoke rather of his descendant, Jesus: he foresaw and spoke of the resurrection of the Messiah.
If Jesus’ body had, like David’s, been known to still be in his tomb, Jesus’ resurrection could have been easily disproved. But Peter’s listeners do not dispute the fact that his tomb was empty. The empty tomb is necessary evidence of Jesus’ resurrection though it is not in itself sufficient to prove it. Belief in Jesus’ resurrection depends on the apostles’ eyewitness testimony that he is alive: of this we are all witnesses.