"He [the Son] says: ‘I will pray the Father, and He shall send you another Comforter…even the Spirit’ [John 14:16f]…. All the Scriptures attest the clear existence of, and distinction in, (the Persons of) the Trinity…. The distinction of Persons in the Trinity, is clearly set forth….
"If the number of the Trinity also offends you as if it were not connected in the simple unity — I ask you how it would be possible for a Being Who was merely and absolutely one and singular, to speak in a plural phrase saying: ‘Let Us make man in Our Own likeness!’ (Genesis 1:26)?… Was it to the angels that He spoke — as the [unitarianized and Judaistic] Jews interpret the passage [as if the creaturely angels co-created man], because these [Judaists] too do not acknowledge the Son?" No!