Jesus was talking about the sacrifice He was going to make and said that no one takes His life away, but that He lays it down on His own initiative. He went on to say that He would lay down His life for His sheep, and also take it up again. No had ever come back from death to eternal life before, and no one has done so since. Anyway, He said that He had this commandment from His Father, and even more astonishing, said that His Father loves Him because He lays down His life for the sheep.