John Calvin on Genesis 7:5

5. And Noah did according to all that the Lord commanded . This is not a bare repetition of the former sentence; but Moses commends Noah’s uniform tenor of obedience in keeping all God’s commandments; as if he would say, that in whatever particular it pleased God to try his obedience, he always remained constant. And, certainly, it is not becoming to obey one or another commandment of God only, so that when we have performed a defective obedience, we should feel at liberty to withdraw; for we must keep in memory the declaration of James,

‘He who forbade thee to kill, forbade thee also to steal, and to commit adultery,’ (James 2:11.)