John 21:18

Thou shalt stretch forth thy hands... signifying by what death he should glorify God; that is, that a cross should be the instrument of his death and martyrdom. --- Whither thou wouldst not: which is no more than to say, that a violent death is against the natural inclination of any man, even though he be ever so willing, and disposed to undergo it. (Witham) --- By this is meant the martyrdom of St. Peter, which took place thirty-four years after this. He was first cast into prison, and then led out to punishment as Christ had foretold him. He stretched out his arms to be chained, and again he stretched them out, when he was crucified; for he died on the cross, as the ancients assure us. (Calmet)