Psalms 71:9

My hope from my youth, "cast me not away in time of old age" [Psalm 71:9]. What is this time of old age? "When my strength shall fail, forsake not me." Here God makes this answer to you, yea indeed let your strength fail, in order that in you mine may abide: in order that you may say with the Apostle, "When I am made weak, then I am mighty." [2 Corinthians 12:10] Fear not, that you be cast away in that weakness, in that old age. But why? Was not your Lord made weak on the Cross? Did not most mighty men and fat bulls before Him, as though a man of no strength, made captive and oppressed, shake the head and say, "If Son of God He is, let Him come down from the Cross"? Has he deserted because He was made weak, who preferred not to come down from the Cross, lest He should seem not to have displayed power, but to have yielded to them reviling? What did He hanging teach you, that would not come down, but patience amid men reviling, but that you should be strong in your God? Perchance too in His person was said, "As it were a monster I have become unto many, and You are a strong Helper." In His person according to His weakness, not according to His power; according to that whereby He had transformed us into Himself, not according to that wherein He had Himself come down. For He became a monster unto many. And perchance the same was the old age of Him; because on account of its oldness it is not improperly called old age, and the Apostle says, "Our old man has been crucified together with Him." [Romans 6:6] If there was there our old man, old age was there; because old, old age. Nevertheless, because a true saying is, "Renewed as an eagle's shall be Your youth;" He rose Himself the third day, promised a resurrection at the end of the world. Already there has gone before the Head, the members are to follow. Why do you fear lest He should forsake you, lest He cast you away for the time of old age, when your strength shall have failed? Yea at that time in you will be the strength of Him, when your strength shall have failed.