Tertullian — Against Praxeas 1

Happy is our sacrament of water, in that, by washing away the sins of our early blindness, we are set free and admitted into eternal life! A treatise on this matter will not be superfluous; instructing not only such as are just becoming formed (in the faith ), but them who, content with having simply believed , without full examination of the grounds of the traditions, carry (in mind), through ignorance , an untried though probable faith . The consequence is, that a viper of the Cainite heresy , lately conversant in this quarter, has carried away a great number with her most venomous doctrine, making it her first aim to destroy baptism . Which is quite in accordance with nature; for vipers and asps and basilisks themselves generally do affect arid and waterless places.

But we, little fishes, after the example of our ΙΧΘΥΣ Jesus Christ , are born in water, nor have we safety in any other way than by permanently abiding in water; so that most monstrous creature, who had no right to teach even sound doctrine, knew full well how to kill the little fishes, by taking them away from the water!