Numbers 9:7
Those 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?”
Exodus 12:27
you shall say, ‘It is the sacrifice of the Lord’s Passover, for He passed over the houses of the Israelites in Egypt when He struck the Egyptians, but spared our houses.’” And the people bowed [their heads] low and worshiped [God].
Numbers 9:2
“The sons of Israel are to keep the Passover at its appointed time.
Deuteronomy 16:2
You shall sacrifice the Passover [lamb] to the Lord your God from the flock or the herd, in the place where the Lord chooses to
2 Chronicles 30:17-19
For there were many in the assembly who had not consecrated themselves [that is, become ceremonially clean and free from all sin]; so the Levites had to slaughter the Passover lambs for everyone who was not clean, in order to make them holy for the Lord.
1 Corinthians 5:7-8