“the Church doth always overlive her enemies; and though the word of God seem oftentimes to be oppressed with the wicked tyranny of men, yet it getteth up the head again by and by, (Romans 8:37.) For Luke determined not only what had happened after that Herod was dead, but also by this example to encourage us, that we may be assured that God will do that, in all ages, which he then did, to the end the gospel may at length break through all impediments of the enemies, and that the more the Church is diminished, it may the more increase through the heavenly blessing.”John Calvin, Commentaries XVIII, 495.
Calvin commenting on Acts 12 captures the real heart of the purpose of the book of Acts. Where it is said above “Luke determined” Calvin footnotes
“Enim consilium Lucae fuit,” for it was the purpose of God.
Acts is an adequate testimony for all nations that not only will God’s truth triumph in the world (cf. Matt 24:14), but increase to the very end of time (cf. Acts 6:7; 12:24; 19:20)!