Irenaeus

For this is the affinity of the apostolical teaching and the most holy “faith delivered unto us,” which the unlearned receive, and those of slender knowledge have taught, not “giving heed to endless genealogies,” but studying rather [to observe] a straightforward course of life; lest, having been deprived of the Divine Spirit, they fail to attain to the kingdom of heaven.

Since the Son of God is always one and the same, He gives to those who believe on Him a well of water [springing up] to eternal life, but He causes the unfruitful fig-tree immediately to dry up; and in the days of Noah He justly brought on the deluge for the purpose of extinguishing that most infamous race of men then existent, who could not bring forth fruit to God, since the angels that sinned had commingled with them, and [acted as He did] in order that He might put a check upon the sins of these men, but [that at the same time] He might preserve the archetype, the formation of Adam. And it was He who rained fire and brimstone from heaven, in the days of Lot, upon Sodom and Gomorrah, “an example of the righteous judgment of God,” that all may know, “that every tree that bringeth not forth good fruit shall be cut down, and cast into the fire.”