Theses theologicae de sacrosancta trinitate contra antitrinitarios

LXVIII.
Whence it must be diligently noted that the name of God is not always to be taken absolutely regarding the essence of the Godhead, but sometimes relatively and determinately, just as the name of Jehovah in the Old Testament, so that it denotes a hypostatic difference.

LXIX.
Thus when Christ is called the Son of the living God, Matt. 16, we say He is the Son not simply of God, but of God the Father.

LXX.
Thus when Paul says that God was manifested in the flesh, 1 Tim. 3, we must understand not simply God (by which reason the Father and the Holy Spirit would also have been incarnate), but the begotten God, that is, the Son, who assumed human nature into the unity of His person, by which He really differs from the Father and the Holy Spirit.

LXXI.
Since many have attempted to pull down the divinity of the Son and the Holy Spirit, we, supported by the illustrious testimonies of Scripture, pronounce that the Son and the Holy Spirit truly exist as consubstantial with and coeternal to the Father.

LXXII.
The most clear testimonies of Scripture show that the Son is God: You are my Son, says God the Father, (Ps. 2), this day I have begotten you. Likewise: You are the Son of the living God, says Peter in Matt. 16; John calls Him the only-begotten of the Father in chapter 1; Paul calls Him His own, that is, His natural Son, Rom. 8.

LXXIII.
But when the Father begot the Son, the λόγος Word, from His own simplest and indivisible substance within His own ἰδίαν own nature, it is necessary that the Son subsists in the same ἰδίᾳ own nature, and is ὁμοούσιον consubstantial to the Father.

LXXIV.
For which cause He is called the brightness of glory and the χαρακτήρ ὑποστάσεως express image of the person of the Father, Heb. 1, for the reason that the same Godhead, omnipotence, and wisdom shines in Him which shines in the hypostasis of the Father.

LXXV.
Explaining this passage elegantly, Oecumenius writes: "The Son is the image original: "χαρακτήρ" of the hypostasis itself, as if He had stamped the whole essence and existence in Himself. He is God, He is authoritative, omnipotent, the creator, and whatever else belongs to the Father, He expresses as an image. Yet the Son is everything that the Father is in being. Therefore, He also provides everything by the word of His power, and sustains and steers it."