John Calvin Commentary Acts 10:20

"But arise, and get thee down, and go with them, nothing doubting: for I have sent them." — Acts 10:20 (ASV)

Go, doubting nothing. The Scripture often uses this phrase when it expresses what kind of obedience faith should produce. So Paul, in Romans 4:19, when he commends the faith of Abraham, says that he did not doubt when the Lord promised him seed, though he was then aged and past the hope of having children.

And in Romans 14:23, when discussing foods, he condemns doubting consciences. Doubting properly means to argue from both sides (as they say), when we are swayed back and forth by considering conflicting reasons. But we must not follow God with a doubtful and wavering mind, but with a quiet and steadfast mind.

In summary, the Lord wants us to attribute so much to Him that, when we hear Him, we no longer dispute what we need to do, but instead establish as a certainty that what He commands must be done. Surely it is fitting that His will should show us the way, once all clouds are driven away, and that it should bring all our senses into submission to it, to willing obedience, all reasoning [disputation] having been broken off.

This principle is also better understood from the following text. For the reason is added why Peter is not permitted to suspend his judgment in an uncertain matter: because God is the author of the affair. This is because it amounts to saying that we ought to be content with God's direction alone, so that we may obey His commandment.

And by this we are also admonished that people's consciences will find peace by no other means, so that they may safely do what they do, than when, being taught by the Word of God, they resolve that they do nothing without His commandment and guidance.