John Calvin Commentary Acts 16:33

"And he took them the same hour of the night, and washed their stripes; and was baptized, he and all his, immediately." — Acts 16:33 (ASV)

He was baptized, and all his household. Luke again commends the godly zeal of the keeper, in that he consecrated his entire household to the Lord. In this, the grace of God also appears, because He brought his whole family to a godly consent.

We must also note the notable change: recently, he was about to kill himself because he thought that Paul and the others had escaped. But now, laying aside all fear, he brings them home.

So we see how faith animates and encourages those to act courageously who previously lacked courage.

And surely, when we are downcast through fear and doubt, there is no better source of boldness than being able to cast all our cares into God’s bosom, so that no danger may terrify us from doing our duty, while we look for an outcome from God’s hand that He will see to be most beneficial.