Therefore doth the Father love me, because I lay down my life, that I may take it again. The διὰ τοῦτο points to the whole of the previous statement, and ὅτι to a more complete exposition of the precise point in it on which the Divine Father's love ( ἀγαπή) rests.
The "I" and "me" refer to the incarnate Son, i.e. to the Divine-human Personality of the Lord Jesus Christ. The Father loveth me, because, not merely that I lay down my life, for such might be the consequence of helplessness in the presence of victorious and desperate foes.
The love which merely "laid down life" would be a Buddha-like self-sacrifice, producing certain moral effects upon the minds of the onlookers, and revealing a large and loving sense of the need of others.
Yet in such expression of his sacrificial love he would have relinquished his undertaking. There would have been no more that he could do for his flock, this Shepherd-functions would, in the consummating act, cease, he would be a beautiful Memory, not a living Energy; a glorious Example, not the Author of eternal salvation.
He would cease to be the great Shepherd of the sheep. Now the Father's love contemplated more than this, viz. the Lord's own purpose to take up again that life which he was prepared voluntarily to lay down for the sheep.
Thus he would indeed die, that he might be more of a Shepherd to them than he had ever been before. How otherwise would he personally bring the other sheep into his flock, or be known of them, as the Father was known by him?
Christ declares that after his death he would still exercise royal rights, be as much a Divine-human Personality as ever. Christ, as a sinless Man, the sinless One, might indeed, after the victory over the tempter in the wilderness, or from the Mount of Transfiguration, have returned to the spiritual world without accomplishing an exodus on Golgotha, but he chose, he willed, to lay down his life.
Having done this much, he might have joined the great majority, and been their Head and Chief, and left his work to be commented on by others. But such a consummation would have fallen far short of the true and sufficing object of the Father's love.
Christ declares that the very end of his death was his resurrection from death. In retaking his life, he is able to continue, on perfectly different terms, the shepherding of his people he becomes in the highest sense, the great Shepherd, the good Shepherd, the archetypal, and the veritable Shepherd of the flock of God.