19. This spake he, signifying by what death he should glorify God--not, therefore, a mere prediction of the manner of his death, but of the honor to be conferred upon him by dying for his Master. And, indeed, beyond doubt, this prediction was intended to follow up his triple restoration:--"Yes, Simon, thou shall not only feed My lambs, and feed My sheep, but after a long career of such service, shalt be counted worthy to die for the name of the Lord Jesus."
      And when he had spoken this, he saith unto him, Follow me--By thus connecting the utterance of this prediction with the invitation to follow Him, the Evangelist would indicate the deeper sense in which the call was understood, not merely to go along with Him at that moment, but to come after Him, "taking up his cross."

JFB.