But it needs some introducing. A vital question in theology is this: does Jesus accurately reveal God to us?
Obviously: yes! After all, in Jesus Christ "the fullness of deity lives in bodily form." (Colossians 2:9)
But so many theologies actually assume that Jesus is kind of "God-lite" - a diet version of God - all the taste but 95% power reduced. You see it whenever people say that Jesus' humility / weakness / sorrow / emotional-life is only true according to his human nature... because God could never be humble / weak / emotional / etc.
Whenever you see this you should ask, "Okay - but how do you know this? How do you know that God could never be such things?" It's the problem of deciding what God is like (based on what is reasonable) before actually approaching the One who is God Revealed.
Karl Barth argued passionately that this approach is wrong. We must let God speak first - because he has in fact spoken first. We must let Jesus define what God is like.
When we do this, we realise that the true God is utterly different from all false gods. All false gods are a projection of our own ideas. The REAL God is proved real because no human would ever imagine a god like him. No human would imagine a Creator God who stoops to be born as man, a man who would glory in the cross. So Barth writes:
What marks out God above all false gods is that they are not capable and ready for this [humility]. In their otherworldliness and supernaturalness and otherness, etc., the gods are a reflection of the human pride which will not unbend, which will not stoop to that which is beneath it. God is not proud. In His high majesty He is humble.
- Karl Barth, Church Dogmatics IV/1, 159.Christmas is approaching - and we remember the King of the world born in humility: Jesus - the most humble man ever to live (Daniel 4:17).
(For another good quote, try here, and spend some time at Christ The Truth also.)