You could say that God gave up His life two times on our behalf: First, He gave up His life as God to be birthed as Jesus of Nazareth in the earth. Second, He gave up His life as Jesus of Nazareth to be raised from the dead to heaven as our God forevermore. It was two different lives with two different deaths – one an echo of the other.
In any case, when He tells us to lay down our lives for the sake of others He is preaching what He has practiced.
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