John 19:33

But when they came to Jesus, and saw that he was dead already, they brake not his legs:

But when they came to Jesus, and saw that he was dead already - for there were in His case elements of suffering unknown to the criminals, which would naturally hasten His death, not to speak of His exhaustion from previous care and suffering, all the more telling on the frame now, from its having been endured in silence.

They brake not his legs - a fact of vast importance, as showing that the reality of His death was visible to those whose business it was to see to it. The other divine purpose served by it will appear presently.