The Prescription Against Heretics by Tertullian
Chapter XXXI.--Truth First, Falsehood Afterwards, as Its Perversion Christ's Parable Puts the Sowing of the Good Seed Before the Useless Tares.
Let me return, however, from this digression to discuss the priority of truth, and the comparative lateness of falsehood, deriving support for my argument even from that parable which puts in the first place the sowing by the Lord of the good seed of the wheat, but introduces at a later stage the adulteration of the crop by its enemy the devil with the useless weed of the wild oats. For herein is figuratively described the difference of doctrines, since in other passages also the word of God is likened unto seed. From the actual order, therefore, it becomes clear, that that which was first delivered is of the Lord and is true, whilst that is strange and false which was afterwards introduced. This sentence will keep its ground in opposition to all later heresies, which have no consistent quality of kindred knowledge inherent in them -- to claim the truth as on their side.