The Son is 'Life' (Jn. 14:6) because He is 'Light', constituting and giving reality to every thinking being. 'For in Him we live, move and exist' (Acts 17:28) and there is a two-fold sense in which He breathes into us (cf. Gen. 2:7; Jn. 20:22); we are filled, all of us, with His breath, and those who are capable of it, all those who open their mind's mouth wide enough, with His Holy Spirit.
Gregory of NazianzusOur starting-point must be the fact that God cannot be named... no mind has yet contained or language embraced God's substance in its fullness. No, we use facts connected with Him to outline qualities that correspond with Him, collecting a faint and feeble mental image from various quarters. Our noblest theologian is not one who has discovered the whole - our earthly shackles do not permit us the whole - but one whose mental image is by comparison fuller, who has gathered in his mind a richer picture, outline, or whatever we call it, of the truth.
Gregory of NazianzusGod always was, and always is, and always will be. Or rather, God always Is. For Was and Will be are fragments of our time, and of changeable nature, but He is Eternal Being. And this is the Name that He gives to Himself when giving the Oracle to Moses in the Mount. For in Himself He sums up and contains all Being, having neither beginning in the past nor end in the future; like some great Sea of Being, limitless and unbounded, transcending all conception of time and nature, only adumbrated [intimated] by the mind, and that very dimly and scantily.
Gregory of NazianzusSuch is the grace and power of baptism; not an overwhelming of the world as of old, but a purification of the sins of each individual, and a complete cleansing from all the bruises and stains of sin. And since we are double-made, I mean of body and soul, and the one part is visible, the other invisible, so the cleansing also is twofold, by water and the Spirit; the one received visibly in the body, the other concurring with it invisibly and apart from the body; the one typical, the other real and cleansing the depths.
Gregory of Nazianzus