Exodus 23:15

15 aYou shall keep the Feast of Unleavened Bread. As I commanded you, you shall eat unleavened bread for seven days at the appointed time in the month of bAbib, for in it you came out of Egypt. cNone shall appear before me empty-handed.

Numbers 9:2-3

2“Let the people of Israel keep the Passover at its appointed time. 3 dOn the fourteenth day of this month, at twilight, you shall keep it at its appointed time; according to all its statutes and all its rules you shall keep it.”

Numbers 9:7

7And those men said to him, “We are unclean through touching a dead body. Why are we kept from bringing the Lord’s eoffering at its appointed time among the people of Israel?”

Numbers 9:13

13But if anyone who is clean and is not on a journey fails to keep the Passover, fthat person shall be cut off from his people because he did not bring the Lord’s goffering at its appointed time; that man shall bear his sin.

Psalms 81:3

3Blow the trumpet at hthe new moon,
at the full moon, on our feast day.
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