New Defender's Study Bible Notes
6:9 generations of Noah. This seems to be Noah’s signature concluding his personal record (Genesis 5:29–6:9a). It is significant that his last word emphasizes only that he was being saved from a sinful world merely by the grace of God.
6:9 perfect in his generations. It is likewise significant that the first sentence of the toledoth of Noah’s sons (note Genesis 10:1) stresses the godliness of their father. Noah is an outstanding example of parental example and guidance. His sons were saved on the ark because of his own righteousness (note Genesis 7:1).