Numbers Chapter 9 Verse 3In the fourteenth day of this month, at even, ye shall keep it in his appointed season: according to all the rites of it, and according to all the ceremonies thereof, shall ye keep it.

And I have given the Levites [as] a gift to Aaron and to his sons from among the children of Israel, to do the service of the children of Israel in the tabernacle of the congregation, and to make an atonement for the children of Israel: that there be no plague among the children of Israel, when the children of Israel come nigh unto the sanctuary.

And Moses, and Aaron, and all the congregation of the children of Israel, did to the Levites according unto all that the LORD commanded Moses concerning the Levites, so did the children of Israel unto them.

And the Levites were purified, and they washed their clothes; and Aaron offered them [as] an offering before the LORD; and Aaron made an atonement for them to cleanse them.

And after that went the Levites in to do their service in the tabernacle of the congregation before Aaron, and before his sons: as the LORD had commanded Moses concerning the Levites, so did they unto them.

And the LORD spake unto Moses, saying,

This [is it] that [belongeth] unto the Levites: from twenty and five years old and upward they shall go in to wait upon the service of the tabernacle of the congregation:

And from the age of fifty years they shall cease waiting upon the service [thereof], and shall serve no more:

But shall minister with their brethren in the tabernacle of the congregation, to keep the charge, and shall do no service. Thus shalt thou do unto the Levites touching their charge.

And the LORD spake unto Moses in the wilderness of Sinai, in the first month of the second year after they were come out of the land of Egypt, saying,

Let the children of Israel also keep the passover at his appointed season.

And Moses spake unto the children of Israel, that they should keep the passover.

And they kept the passover on the fourteenth day of the first month at even in the wilderness of Sinai: according to all that the LORD commanded Moses, so did the children of Israel.

And there were certain men, who were defiled by the dead body of a man, that they could not keep the passover on that day: and they came before Moses and before Aaron on that day:

And those men said unto him, We [are] defiled by the dead body of a man: wherefore are we kept back, that we may not offer an offering of the LORD in his appointed season among the children of Israel?

And Moses said unto them, Stand still, and I will hear what the LORD will command concerning you.

And the LORD spake unto Moses, saying,

Speak unto the children of Israel, saying, If any man of you or of your posterity shall be unclean by reason of a dead body, or [be] in a journey afar off, yet he shall keep the passover unto the LORD.

The fourteenth day of the second month at even they shall keep it, [and] eat it with unleavened bread and bitter [herbs].

They shall leave none of it unto the morning, nor break any bone of it: according to all the ordinances of the passover they shall keep it.

But the man that [is] clean, and is not in a journey, and forbeareth to keep the passover, even the same soul shall be cut off from among his people: because he brought not the offering of the LORD in his appointed season, that man shall bear his sin.

The Book of Numbers, Chapter 9, Verse 3