23. The fourth book starts with the doctrines of the heretics, and disowns complicity in the fallacies whereby they are traducing the faith of the Church. It publishes that infidel creed which a number of them have lately promulgated13    The letter of Arius to Alexander; Book iv., §§ 12, 13., and exposes the dishonesty, and therefore the wickedness, of their arguments from the Law for what they call the unity of God. It sets out the whole evidence of Law and Prophets to demonstrate the impiety of asserting the unity of God to the exclusion of the Godhead of Christ, and the treason of alleging that if Christ be God the Only-begotten, then God is not one.

23. Liber quartus.---Quartus deinde liber initium sui ex haereticorum doctrinis auspicatur, se ipsum vitiis, quibus fides Ecclesiae infamatur, expurgans: ipsam illam perfidiae expositionem a multis non 0040A olim editam proferens, et subdole eos, ac per id impiissime, unum Deum ex lege defendisse convincens, omnibus legis ac prophetarum testimoniis ita demonstratis, ut sine Deo Christo unum Deum confiteri irreligiositas sit; et confesso unigenito Deo Christo, non unum Deum praedicare perfidia sit.