The Epistle to Diogentus (7.2)

But in truth the Almighty and all-creating and invisible God himself founded among

men the truth from heaven, and the holy and incomprehensible word, and established it in their hearts, not, as one might suppose, by sending some minister to men, or an angel, or ruler, or one of those who direct earthly things, or one of those who are entrusted with the dispensations in heaven, but the very artificer and Creator of the universe himself, by whom he made the heavens, by whom he enclosed the sea in its own bounds, whose mysteries all the elements guard faithfully; from whom the sun received the measure of the courses of the day, to whose command the moon is obedient to give light by night, whom the stars obey, following the course of the moon, by whom all things were ordered, and ordained, and placed in subjection, the heavens and the things in the heavens, the earth and the things in the earth, the sea and the things in the sea, fire, air, abyss, the things in the heights, the things in the depths, the things between them—him he sent to them.