Leviticus 23:14-16

Amplified Bible

¹⁴ You shall not eat any bread or roasted grain or new growth, until this same day when you bring in the offering to your God; it is a permanent statute throughout your generations wherever you may be.

The Feast of Weeks

¹⁵ ‘You shall count from the day after the Sabbath, from the day when you brought in the sheaf (tied bundle of grain) of the wave offering; there shall be seven complete Sabbaths (seven full weeks). ¹⁶ You shall count ^[a]fifty days to the day after the seventh Sabbath; then you shall present a new grain offering to the Lord.