John Calvin Commentary Acts 7:20

"At which season Moses was born, and was exceeding fair; and he was nourished three months in his father`s house." — Acts 7:20 (ASV)

It is for good reason that Stephen notes the circumstance of time. Moses was born at the very time the king had commanded that all the male children should be cast out. Therefore, it seems that the minister of deliverance is dead before he is born. But that time is most fitting for God to work, when there is no hope or counsel to be looked for from human hands.

And it also appears most plainly how God perfects His power in human weakness (2 Corinthians 12:9). Moses is kept for three months, but eventually his parents (so that they may save their own lives) are forced to cast him out into the river. They only put him into a small basket, so that he might not immediately perish.

When Pharaoh’s daughter takes him up, he indeed escaped death, yet in such a way that he goes into another nation, being cut off from the kin of Israel. Indeed, he was likely to be a most troublesome adversary to his nation, unless God had restrained his mind. It is forty years before he shows any sign of brotherly goodwill.