He who retains unchangeable in his heart the rule of the truth which he received by means of baptism will doubtless recognise the names, the expressions, and the parables taken from the Scriptures [by the gnostics], but will by no means acknowledge the blasphemous use which these men make of them.

Error never shows itself in its naked reality, in order not to be discovered. On the contrary, it dresses elegantly, so that the unwary may be led to believe that it is more truthful than truth itself.

Error, indeed is never set forth in its naked deformity, lest, being thus exposed, it should at once be detected. But it is craftily decked out in an attractive dress, so as, by its outward form, to make it appear to the inexperienced more true than truth itself.

[Peter] testified to [the Jews in Acts 2] that Jesus Christ was the Son of God, the Judge of the living and dead, into whom he did also command them to be baptized for the remission of sins.

The initial step for us all to come to knowledge of God is contemplation of nature.

Others of them employ outward marks ... They style themselves Gnostics. They also possess images, some of them painted and others formed from different kinds of material. They maintain that a likeness of Christ was made by Pilate at that time when Jesus lived among them. They crown these images, and set them up along with the images of the philosophers of the world, such as Pythagoras, Plato, and Aristotle, and the rest. They have also other modes of honoring these images just like the Gentiles.

One should not seek among others the truth that can be easily gotten from the Church. For in her, as in a rich treasury, the apostles have placed all that pertains to truth, so that everyone can drink this beverage of life. She is the door of life.