Numbers 9:13-14 (NKJV)
But the man who is clean and is not on a journey, and ceases to keep the Passover, that same person shall be cut off from among his people, because he did not bring the offering of the Lord at its appointed time; that man shall bear his sin.
'And if a stranger dwells among you, and would keep the Lord 's Passover, he must do so according to the rite of the Passover and according to its ceremony; you shall have one ordinance, both for the stranger and the native of the land.' "
I am fascinated by two ideas in these obscure verses deep in the middle of all the "boring" Levitical laws that no one ever preaches on or reads. First of all, remember that the Passover is an Old Testament picture of the coming sacrifice of our Lord Jesus Christ.
Now, notice that if someone failed to keep the Passover ordinances that he will be cut off from his people and he will have to bear his own sin. Going to the real meaning, we see that if someone were to reject Jesus and what he did for us, that he would be "cut" off from among God's people. That is to say, he would spend eternity cut off from God's presence which is hell. Moreover, he would have to bear his own sin instead of choosing to accept Jesus' offer of bearing his sin for him.
Now in the second verse, notice that even a stranger must obey the ordinance in exactly the same way as the people of God. Every one must come to God the same way, through the sacrificial blood atonement of Jesus Christ.