Further gloss on constraint...

"Let each of you look not to your own interests, but to the interests of others. Let the same mind be in you that was in Christ Jesus, who, though he was in the form of God, did not regard equality with God as something to be exploited, but emptied himself, taking the form of a slave, being born in human likeness. And being found in human form, he humbled himself and became obedient to the point of death— even death on a cross." - Paul, in the letter to the Philipians, 2.6-10