We keep the day of Pentecost on the 50th day following the Sabbath that occurs during the Days of Unleavened Bread (see Leviticus 23:15). However, once in every nine years (on average) an unusual phenomenon occurs. The Sabbath that occurs within the Feast of Unleavened Bread falls on the last day of Unleavened Bread. On these years, many churches count Pentecost from the first day of Unleavened Bread (a Sunday), even though the Sabbath from which they count occurs on the day of the Passover, which is not part of the Feast. In these years, we count from the next Sabbath, which does fall within the Feast of Unleavened Bread, causing Pentecost to occur one week later. This method of counting to Pentecost is in accord with all the biblical instruction regarding Pentecost, its counting, and the requirements for the wave sheaf offering. This phenomenon happens again in 2021 and 2025.