The Epistles of Ignatius

I therefore, yet not I, but the love of Jesus Christ, entreat you that ye use Christian nourishment only, and abstain from herbage of a different kind; I mean heresy. For those [that are given to this] mix up Jesus Christ with their own poison, speaking things which are unworthy of credit, like those who administer a deadly drug in sweet wine, which he who is ignorant of does greedily take, with a fatal pleasure leading to his own death.