Numbers 9:5-7

Revised Standard Version

⁵ And they kept the passover in the first month, on the fourteenth day of the month, in the evening, in the wilderness of Sinai; according to all that the Lord commanded Moses, so the people of Israel did. ⁶ And there were certain men who were unclean through touching the dead body of a man, so that they could not keep the passover on that day; and they came before Moses and Aaron on that day; ⁷ and those men said to him, “We are unclean through touching the dead body of a man; why are we kept from offering the Lord’s offering at its appointed time among the people of Israel?”