Exodus 34:8

And Moses made haste, and bowed his head — Thus he expressed his humble reverence and adoration of God's glory, together with his joy in this discovery God had made of himself, and his thankfulness for it. Then likewise he expressed his holy submission to the will of God made known in this declaration, subscribing to his justice as well as mercy, and putting himself and his people Israel under the government of such a God as Jehovah had now proclaimed himself to be. Let this God be our God for ever and ever!