Jesus did not simply act for God in the world he acted as God. He is the very action of God himself in our world. So, to know what God is like we fix our eyes on Jesus as God’s action in the world.
But is this where we usually begin when considering who God is. I think too many of us begin with abstract ideas about the divine being. God is infinite, eternal, unchanging and so on. He is omnipotent, omnipresent, and omniscient. We think this is the real “stuff” of divinity.
But is this the way God has made himself known? John tells us, “No one has ever seen God. It is God the only Son, who is close to the Father’s heart, who has made him known” (John. 1.18). Who is the one true God? What is the “divine nature”? We do not discover the answer to these questions from our own notions of supreme, absolute, non-worldly, perfect being. We only know what God is like through Jesus’ human actions as God. From what he has done and suffered as human. For Jesus is God as human, among humans and for humans.
The same Jesus who came into the world comes to us by the Spirit. He encounters us personally as the Living Lord who always surpasses our knowing. And so we don’t decide what God is like out of our own darkness. Rather, “God, who said, “Let light shine out of darkness,” made his light shine in our hearts to give us the light of the knowledge of God’s glory displayed in the face of Christ” (2 Cor. 4.6).