I think Philippians 2:5-7 helps expain:
1. Jesus was in form of God = Equal. (John 1 he was creator, etc)
2. Did not regard equality with God a thing to be grasp
3. He willing made himself lower for a little while taking on the form of man in the flesh.
Phil 2:5 Have this attitude in yourselves which was also in Christ Jesus, 6 who, although He existed in the form of God, did not regard equality with God a thing to be grasped, 7 but emptied Himself, taking the form of a bond-servant, and being made in the likeness of men. 8 Being found in appearance as a man, He humbled Himself by becoming obedient to the point of death, even death on a cross.