Numbers 9:6-12

6But there were certain men who were [ceremonially] unclean because of [touching] the dead body of a man, so they could not observe the Passover on that day; so they came before Moses and Aaron that same day.

7Those men said to Moses, “We are [ceremonially] unclean because of [touching] a dead body. Why are we being restrained from presenting the Lord’s offering at its appointed time among the Israelites?”

8Therefore, Moses said to them, “Wait, and I will listen to what the Lord will command concerning you.”

9Then the Lord spoke to Moses, saying,

10“Say to the Israelites, ‘If any one of you or of your descendants becomes [ceremonially] unclean because of [touching] a dead body or is on a distant journey, he may, however, observe the Passover to the Lord.

11On the fourteenth day of the second month [thirty days later] at twilight, they shall observe it; they shall eat it with unleavened bread and bitter herbs.

12They shall leave none of it until morning nor break any of its bones; in accordance with all the statutes of the Passover they shall observe it.