Great comments by John Piper from his latest sermon:
“But you do not believe, because you are not part of my flock. My sheep hear my voice, and I know them, and they follow me. I give them eternal life, and they will never perish, and no one will snatch them out of my hand. My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father’s hand. I and the Father are one.”
Notice three things. First, when the Father gives his sheep into the omnipotent hand of the Son, they are still in the Father’s hand. Verse 29: “My Father, who has given them to me, is greater than all, and no one is able to snatch them out of the Father’s hand.” Even though the Father has put them into the Son’s hand, they are in the Father’s hand. What does this imply?
Second, notice that Jesus explains this with the words of verse 30: “I and the Father are one.” His final answer about his identity is way beyond messiahship. It is oneness with God the Father.
And third, notice that Jesus takes us to this answer by showing how this oneness serves our salvation—our eternal safety and joy. The Father and I are one. No one can take you from me because I am stronger than all. And no one can take you from my Father, because my Father is stronger than all. When you are in my hand, you are in his hand, and when you are in his hand, you are in my hand. Our omnipotence, and our unity are your safety, your salvation.
Now there is a lesson here, and I want to drive it home. Jesus takes us to the heights of doctrinal truth about himself. He is one with the Father. “In the beginning was the word and the word was with God and the word was God. . . . And the Word became flesh” (John 1:1, 14). But he does it by showing us the immediate implication for our lives: No one can snatch you from my hand. Or the Father’s hand. Which are one hand. In other words, doctrine, theology, biblical propositions (like “I and the Father are one”) are always related to their implications for human life. Don’t be afraid of doctrine. Just be afraid of disconnected doctrine. Doctrine that doesn’t make a difference for life and eternity.