16. The voice of the warning apostle is, “Purge out the old leaven, that ye may be a new lump, as ye are unleavened; for even Christ our passover is sacrificed. Therefore let us keep the feast, not with old leaven, neither with the leaven of malice and wickedness, but with the unleavened bread of sincerity and truth.”31 1 Cor. v. 7. But are sincerity and truth preserved, when what is sincere is polluted by adulterous colours, and what is true is changed into a lie by the deceitful dyes of medicaments? Your Lord says, “Thou canst not make one hair white or black;”32 Matt. v. 36. and you, in order to overcome the word of your Lord, will be more mighty than He, and stain your hair with a daring endeavour and with profane contempt. With evil presage of the future, you make a beginning to yourself already of flame-coloured hair; and sin (oh, wickedness!) with your head—that is, with the nobler part of your body! And although it is written of the Lord, “His head and His hair were white like wool or snow,”33 Apoc. i. 14. you curse that whiteness and hate that hoariness which is like to the Lord’s head.
XVI. Monentis Apostoli vox est: Expurgate vetus fermentum, ut sitis nova conspersio, sicut estis azymi . Nam et pascha nostrum immolatus est Christus. Itaque festa celebremus , non in fermento vetere, neque in fermento malitiae et nequitiae, sed in azymis sinceritatis et veritatis (I Cor. V, 7). Num sinceritas perseverat et veritas quando quae sincera sunt polluuntur colorum adulteriis , et adulterinis medicaminum fucis in mendacium vera mutantur? Dominus tuus dicit: Non potes facere capillum unum album aut nigrum (Matth. V, 0455C 36): et tu ad vincendam Domini tui vocem vis te esse 0456A potiorem? Audaci conatu et sacrilego contemptu crines tuos inficis, malo praesagio futurorum capillos jam tibi flammeos auspicaris, et peccas, proh nefas! capite , id est corporis parte meliore. Et cum scriptum sit de Domino: Caput autem ejus et capilli erant albi velat lana aut nix (Apoc. I, 14), tu execraris canitiem, detestaris alborem qui sit ad Domini caput similis.