 Think about it logically. If God is one, the one, the absolute existence, the absolute reality, and every single existence of ours is contingent upon Him. He is the only true reality. He is the only true existence. Why would He need them to humble Himself? With this knowledge of knowing that He is all-powerful, that there are absolutely no competitors for Him, nobody can compete with God. He is the beginning and the end. Why would such a God need to humble Him?