Numbers 9:4-6

International Standard Version

⁴ So Moses instructed the Israelis to observe the Passover. ⁵ They observed the Passover on the fourteenth day of the first month at twilight, in the Wilderness of Sinai. The Israelis did everything that the Lord had commanded through Moses.

Special Passover Rules

⁶ But there were men who couldn’t observe the Passover that day because they had come in contact with a corpse. That very day, they approached Moses and Aaron