Herod sees an opportunity to get favor from the Jews, by persecuting the church. (This means hostility from Jew to Christian was getting intense and widespread.) He kills James, brother of John (not of Jesus, not the author of the book following Hebrews), and imprisons Peter. God frees Peter, with lots of Passover overtones (angel, door, sandals and cloaks, death of enemies).
Herod later dies, receiving idolatrous worship without stopping it.
The Word of God grows while its enemies are left in the dust.
Barnabas & Saul are a new Moses, mediating a new covenant to a new people, after a new Passover.