And just as then, those who led vicious lives, and put other people astray, were condemned and cast out, so also even now the offending eye is plucked out, and the foot and the hand, lest the rest of the body perish in like manner. And we have the precept: "If any man that is called a brother be a fornicator, or covetous, or an idolater, or a railer, or a drunkard, or an extortioner, with such an one no not to eat." And again does the apostle say, "Let no man deceive you with vain words; for because of these things cometh the wrath of God upon the sons of mistrust. Be not ye therefore partakers with them." And as then the condemnation of sinners extended to others who approved of them, and joined in their society; so also is it the case at present, that "a little leaven leaveneth the whole lump." And as the wrath of God did then descend upon the unrighteous, here also does the apostle likewise say: "For the wrath of God shall be revealed from heaven against all ungodliness and unrighteousness of those men who hold back the truth in unrighteousness."
Source: Irenaeus Against Heresies Book 4