Leviticus 23:13-15

Amplified Bible

¹³ Its grain offering shall be two-tenths of an ephah of fine flour mixed with [olive] oil, an offering by fire to the Lord for a sweet and soothing aroma, with its drink offering [to be poured out], a fourth of a ^[a]hin of wine. 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).