Exodus 12:43-51

43 And the Lord said to Moses and Aaron, “This is the statute of the Passover: no foreigner shall eat of it, 44 but every slave that is bought for money may eat of it after you have circumcised him. 45 No foreigner or hired worker may eat of it. 46 It shall be eaten in one house; you shall not take any of the flesh outside the house, and you shall not break any of its bones. 47 All the congregation of Israel shall keep it. 48 If a stranger shall sojourn with you and would keep the Passover to the Lord, let all his males be circumcised. Then he may come near and keep it; he shall be as a native of the land. But no uncircumcised person shall eat of it. 49 There shall be one law for the native and for the stranger who sojourns among you.” 50 All the people of Israel did just as the Lord commanded Moses and Aaron. 51 And on that very day the Lord brought the people of Israel out of the land of Egypt by their hosts.

The Lord gives seven rules here to make it clear to the Israelites how they should keep the Passover, and why it matters. Note that only the covenant people are to keep it—either you are all-in, or you’re not. Did you see that note about not breaking the bones of the lamb? In the Gospel of John, the author makes a point of connecting that verse to the sacrificial death of Jesus:

31 Now it was the day of Preparation, and the next day was to be a special Sabbath. Because the Jewish leaders did not want the bodies left on the crosses during the Sabbath, they asked Pilate to have the legs broken and the bodies taken down. 32 The soldiers therefore came and broke the legs of the first man who had been crucified with Jesus, and then those of the other. 33 But when they came to Jesus and found that he was already dead, they did not break his legs.34 Instead, one of the soldiers pierced Jesus’ side with a spear, bringing a sudden flow of blood and water. 35 The man who saw it has given testimony, and his testimony is true. He knows that he tells the truth, and he testifies so that you also may believe. 36 These things happened so that the scripture would be fulfilled: “Not one of his bones will be broken,” 37 and, as another scripture says, “They will look on the one they have pierced.” [John 19:31-37]

This reference back to Exodus in the Gospel of John is a great example of the principle that every word in scripture matters.