The trinity is a difficult concept.
But if Jesus wasn't God, how did He live a completely sinless life?
I believe he was God incarnate, thus man AND God.
God through His Holy Spirit allowed Mary (a human) to give birth to Jesus.
So Jesus was both God and human.
It's like 2 human parents create (and one give) birth to human children. 2 dog "parents" create a dog. A lion and a tiger create a liger....
Jesus' father was God and His mother was mary, thus He was both God and human.
That's the way I see it anyway