Charles Ellicott Commentary Numbers 28:26

"Also in the day of the first-fruits, when ye offer a new meal-offering unto Jehovah in your [feast of] weeks, ye shall have a holy convocation; ye shall do no servile work;" — Numbers 28:26 (ASV)

In the day of the firstfruits.— See Exodus 23:16; Exodus 34:22; Leviticus 23:15–21, and Notes.

A new meat offering ... — See Leviticus 23:16.

After your weeks be out.— Hebrew, in your weeks — that is, at the expiration of a week of weeks from the day after the chief day of the feast of the Passover.