Numbers 9:6-12
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:
Nave's Topical Index—AKJV

2 Chronicles 30:2-4
For the king had taken counsel, and his princes, and all the congregation in Jerusalem, to keep the passover in the second month.
Nave's Topical Index—AKJV