Q: Gregory of Nazianzus, why is Jesus called the "image of the invisible God" (Col 1:15)?
A: "He is called 'image' because he is of the same essence as the Father and springs from him, while the Father does not spring from him. It is true that it is the nature of every image to be a likeness of an original, but here we have more. Normally, there is the lifeless [image] of a living being, but here we have the living [image] of a living being, much more similar than Seth is similar to Adam, or the offspring to his parent. Noncomposite things by their nature do not resemble each other in this but not in that; instead, one thing as a whole is a likeness of another as a whole, or rather: the one is identical to the other; it is not an imitation."