Tertullian — on Rom 2:16 (Against Marcion Book V)

“Now he did not observe how much this clause of the sentence made against him: "For God, who commanded the light to shine out of darkness, hath shined in our hearts, to (give) the light of the knowledge (of His glory) in the face of (Jesus) Christ." Now who was it that said; "Let there be light? " And who was it that said to Christ concerning giving light to the world: "I have set Thee as a light to the Gentiles" -to them, that is, "who sit in darkness and in the shadow of death? " (None else, surely, than He), to whom the Spirit in the Psalm answers, in His foresight of the future, saying, "The light of Thy countenance, O Lord, hath been displayed upon us.”