In one house shall it be eaten; you shall not carry forth any of the flesh outside of the house; neither shall you break a bone of it.
All Commentaries on Exodus 12:46 Go To Exodus 12
Augustine of Hippo
AD 430
Now next, that the legs of those two were broken, while his [Christ’s] were not. He was already dead. Why this happened was stated in the Gospel itself. It was fitting, you see, to demonstrate by this sign as well that the true point and purpose of the Jewish Passover, which contained this instruction, not to break the lamb’s bones, was to be a prophetic preenactment of his death.