And we are witnesses of all things which he did both in the land of the Jews, and in Jerusalem; whom they slew and hanged on a tree:

ACTS 10:39KJV
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What does Acts 10:39 mean?

Acts 10:39 means that the apostles personally saw everything Jesus did among the Jewish people and in Jerusalem, and they testify that he was killed by being hung on a tree. This verse highlights the role of the apostles as eyewitnesses to both Jesus’s ministry and his death.

Peter is speaking to Cornelius and his household, explaining the story of Jesus to Gentiles who are hearing it for the first time. Peter stresses that he and the other apostles did not hear these things secondhand—they were present for Jesus’s actions and for his crucifixion, which he describes as being “hanged on a tree,” a phrase that echoes the shameful and public nature of Jesus’s death.