Numbers 9:4

"And Moses spake unto the children of Israel, that they should keep the Passover. And they kept the Passover in the first month, on the fourteenth day of the month, at even, in the wilderness of Sinai: according to all that Jehovah commanded Moses, so did the children of Israel. And there were certain men, who were unclean by reason of the dead body of a man, so 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 unclean by reason of the dead body of a man: wherefore are we kept back, that we may not offer the oblation of Jehovah in its appointed season among the children of Israel? And Moses said unto them, Stay ye, that I may hear what Jehovah will command concerning you."

"At even ..." (Numbers 9:5). "This is literally `between the two evenings',"[9] and was understood differently in different ages. About the first century A.D., it meant, "the time between three and five o'clock in the evening."[10] Since our Lord died at 3:00 p.m., this fact regarding the True Lamb makes it likely that this was the intended hour from the first.

As frequently observed in Numbers, additional instruction regarding some previous regulation resulted from some emergency need for further clarification; and, in these verses, a similar instance arose. Certain men came to Moses and presented the problem caused by their uncleanness from touching a dead body, with a result that they were ceremonially forbidden to take the Passover at the proper time. Moses did not presume to answer this "from his experience," or from his own conclusions. He promptly commanded the men to wait until GOD would speak concerning their problem. "These men were probably Mishael and Elizaphan, who buried their cousins, Nadab and Abihu, within a week of when this Passover was held (Leviticus 10:4,5)."[11]