To answer "What did Christ lose?"
I’d say: His life - as a Man - by terrible sufferings.
He willingly gave up his life, so that we might have eternal Life.
Jesus suffered, not merely as Man, but also as God.
He knew how much He had to suffer for the sins of the whole world - for all time. Because of this fore-knowledge, Jesus must have suffered at least twice. First during his prayers in the Garden of Olives, and again when what He foresaw became actuality: the flogging, a crown of thorns beaten into His head, the carrying of the cross on a body that was one open wound, the crucificion itself.
Because of this foreknowledge of his impending sufferings, Jesus sweated blood. I don’t know, or have never heard of anyone sweating blood like Jesus did. (Probably mystics, but that’s another story.)
Jesus, as God, is a Being with unlimited capacities. His suffering must have been expecienced on severly spiritual levels in the most intense, unlimited way, unfathomably to mere human beings. Jesus’ whole Life can be considered a Life of Suffering. Consider the hardships (hunger, thirst, no comfortable places to sleep while on his many exhausting travels), ridicule, humiliations, ungratefulness, and many other things.
By the sacrifice of giving up his earthly life, flesh was united with the spiritual. That’s why we can receive Jesus wholly in Holy Communion - Body and Blood (flesh), His Soul and Divinity. Not just in a spiritual manner.
I think all this adds up to one HUGE Sacrifice.
Jesus lost his Life, in order to give men Eternal Life.