Matthew Henry on Genesis 6:8-10
We have here Noah distinguished from the rest of the world, and a peculiar mark of honour put upon him. 1. When God was displeased with the rest of the world, he favoured Noah: But Noah found grace in the eyes of the Lord, Gen 6:8. This vindicates God's justice in his displeasure against the world, and shows that he had strictly examined the character of every person in it before he pronounced it universally corrupt; for, there being one good man, he found him out, and smiled upon him. It also magnifies his grace towards Noah that he was made a vessel of God's mercy when all mankind besides had become the generation of his wrath: distinguishing favours bring under peculiarly strong obligatio…
Read the whole note in the consoleJamieson-Fausset-Brown on Genesis 6:9
Noah . . . just . . . and perfect--not absolutely; for since the fall of Adam no man has been free from sin except Jesus Christ. But as living by faith he was just (Gal 3:2; Heb 11:7) and perfect--that is, sincere in his desire to do God's will.
Adam Clarke on Genesis 6:8
Noah found grace in the eyes of the Lord - Why? Because he was, 1. A just man, איש צדיק ish tsaddik, a man who gave to all their due; for this is the ideal meaning of the original word. 2. He was perfect in his generation - he was in all things a consistent character, never departing from the truth in principle or practice. 3. He walked with God - he was not only righteous in his conduct, but he was pious, and had continual communion with God. The same word is used here as before in the case of Enoch. See Gen 5:22.
John Gill on Genesis 6:10
And Noah begat three sons, Shem, Ham, and Japheth. When he was five hundred years of age, and before the flood came upon the earth; and when it was so wicked as is next described: of these sons of his, and of the order in which they are placed; see Gill on Genesis 5:32.
John Calvin on Genesis 6:9-10