Matthew Poole and continuators on John 21:19

19 This spake he, signifying by what death he should glorifie God. And when he had spoken this, he saith unto him, Follow me .

This 19. verse, gives us the general scope of verse 18. viz. That it was a prediction of that particular death by which Peter should die, which was (if we may believe, what the Ancients have generally reported, and we can have no other proof) by Crucifying; in which kind of death, the hands of the person Crucified, are stretched out and nailed to the Cross. But which way he died, we cannot certainly affirm; the Evangelist assureth us, that our Saviour spake these words, with reference to that kind of death, by which Peter as a martyr was to glorifie God; nor is it any objection against his martyrdom, that our Saviour here saith, that he should be carryed whither he would not: for he was not better than his Lord, whose Spirit was willing, and Flesh weak. Whether our Saviour by this command, Follow me, intended the imitation of him, his death, or the particular kind of his death, is uncertain; unless we will allow this Text to be interpreted by Chap. 13.36. and 2 Pet. 1.14.

Marginal references: 2 Pet. 1.14.