Exodus 34:23-25

American Standard Version

²³ Three times in the year shall all thy males appear before the Lord Jehovah, the God of Israel. ²⁴ For I will cast out nations before thee, and enlarge thy borders: neither shall any man desire thy land, when thou goest up to appear before Jehovah thy God three times in the year.

²⁵ Thou shalt not offer the blood of my sacrifice with leavened bread; neither shall the sacrifice of the feast of the passover be left unto the morning.