Letter on the Council of Nicaea

⁶ In the same way we also admitted “begotten, not made;” since the Council alleged that “made” was an appellative common to the other creatures which came to be through the Son, to whom the Son had no likeness. Wherefore, say they, He was not a work resembling the things which through Him came to be, but was of an essence which is too high for the level of any work; and which the Divine oracles teach to have been generated from the Father, the mode of generation being inscrutable and incalculable to every originated nature.