25. There remains, I conceive, no possibility of doubt but that the words, I and the Father are One, were spoken with regard to the nature which is His by birth. The Jews had rebuked Him because by these words He, being a man, made Himself God. The course of His answer proves that, in this I and the Father are One, He did profess Himself the Son of God, first in name, then in nature, and lastly by birth. For I and Father are the names of substantive Beings; One is a declaration of Their nature, namely, that it is essentially the same in Both; are forbids us to confound Them together; are one, while forbidding confusion, teaches that the unity of the Two is the result of a birth. Now all this truth is drawn out from that name, the Son of God, which He being sanctified by the Father, bestows upon Himself; a name, His right to which is confirmed by His assertion, I and the Father are One. For birth cannot confer any nature upon the offspring other than that of the parent from whom that offspring is born.
25. EGO ET PATER UNUM SUMUS, naturam nativitatis ostendit.---Non est relictus, ut arbitror, ambigendi 196 locus, quin de natura nativitatis dictum sit: Ego et Pater unum sumus. Nam cum Judaei arguissent illum, quod per hoc dictum, homo ipse cum esset, sese Deum faceret: responsio ejus confirmat, quod Dei se filium per id quod Ego et Pater unum sumus (Joan. X, 30), ostenderit, primum nomine, deinde natura, postremo nativitate. Nam ego et Pater rerum nomina 0221B sunt; unum vero naturae professio est, quia in eo quod est uterque non differat; sumus autem non patitur unionem. Et ubi quod unum sumus unio non est, unum eos efficit esse nativitas. Hoc enim totum ex eo est, quod Dei se filium sanctificatus a Patre profitetur, et professio Dei filii hoc quod Ego et Pater unum sumus confirmat: quia nativitas non aliam possit, nisi eam ex qua subsistit, afferre naturam.