John 19:33 - Ellicott's Commentary On The Whole Bible

And saw that he was dead already,... The only explanation of their not breaking the legs of Jesus seems to be that the purpose of the crurifragium was to ensure death, or, in any case, prevent the possibility of escape. Crucifixion itself would not necessarily cause death for several days, nor, indeed, at all; but Jesus had by His own will committed His spirit to His Father.