Animal men, again, are instructed in animal things; such men, namely, as are established by their works, and by a mere faith, while they have not perfect knowledge. We of the Church, they say, are these persons. Wherefore also they maintain that good works are necessary to us, for that otherwise it is impossible we should be saved. But as to themselves, they hold that they shall be entirely and undoubtedly saved, not by means of conduct, but because they are spiritual by nature. For, just as it is impossible that material substance should partake of salvation (since, indeed, they maintain that it is incapable of receiving it), so again it is impossible that spiritual substance (by which they mean themselves) should ever come under the power of corruption, whatever the sort of actions in which they indulged. For even as gold, when submersed in filth, loses not on that account its beauty, but retains its own native qualities, the filth having no power to injure the gold, so they affirm that they cannot in any measure suffer hurt, or lose their spiritual substance, whatever the material actions in which they may be involved.
IRENÆUS: Against Heresies: Book I