Exodus:34:22-24
jps@Exodus:34:22 @ And thou shalt observe the feast of weeks, even of the first-fruits of wheat harvest, and the feast of ingathering at the turn of the year.
jps@Exodus:34:23 @ Three times in the year shall all thy males appear before the Lord GOD, the God of Israel.
jps@Exodus:34:24 @ For I will cast out nations before thee, and enlarge thy borders; neither shall any man covet thy land, when thou goest up to appear before the LORD thy God three times in the year.