From the Canon at Matins during the Pre-feast of the Nativity:
"You, the Word without beginning and one in nature with the Father, were laid in a manger of irrational beasts and freed from unreason us who celebrate devoutly the Forefeast of your Nativity."
God became man to make man God. He came to us in the Flesh in Bethlehem to join us in the Flesh to Him in the Eucharist. He came not to reassure us, or support us in what we were doing of our own accord, but to convert us from where we were. Seeing us living lives of sin and hating sin, He came to convert us and liberate us from the tyranny of sin, for were created for the sole purpose of being with Him and He came to show us this, our true origins and purpose, and to bring us to Himself, out of the falsehood and deception of sin.