And spared not the old world: the world, for men in the world, viz. those that lived in it before the flood. But saved Noah the eighth person; viz. together with the other seven, his wife, three sons, and their wives, 1 Peter 3:20. Noah may be particularly named, because God had a special respect to him, and for his sake spared others. A preacher: constituted to be so by Divine authority and commission. Of righteousness: i.e. not only:
1. Of the righteousness of God, who had threatened to destroy the world for its wickedness; but:
2. Of the righteousness of Christ upon all them that should believe. It is not to be doubted but he preached the same righteousness whereof he himself was heir, and that was the righteousness of faith, Hebrews 11:7; and this he did not in words only, but in his actions; in that he built the ark for the saving himself and his household, which was a type of the salvation of believers by Christ. And:
3. Of the righteousness of sanctification, in his exhorting the men that then were to repentance and holiness, if possibly thereby they might prevent the approaching deluge. Bringing in the flood upon the world of the ungodly; the whole multitude of wicked men then living in the world.