John of Damascus — on Ps 135:6 (ORTHODOX FAITH 2:29)

“Providence, then, is the solicitude that God has for existing things. And again, providence is that will of God by which all existing things receive suitable guidance through to their end. But, if providence is God's will, then, according to right reason, everything that has come about through providence has quite necessarily come about in the best manner and that most befitting God, so that it could not have happened in a better way. Now, the Maker of existing things must be the same as their Provider, for it is neither fitting nor logical that one should be their creator and another their provider, because in such a case they would both be definitely wanting—the one in the matter of creating and the other in that of providing. Hence, God is both Creator and Provider, and his power of creating, sustaining and providing is his good will. For "whatsoever the Lord pleased he has done, in heaven and in earth," and none resisted his will. He willed all things to be made, and they were made; he wills the world to endure, and it does endure; and all things whatsoever he wills are done.”