Deuteronomy 16:8-9

Six days thou shalt eat unleavened bread: and on the seventh day {shall be} a solemn assembly to the LORD thy God: thou shalt do no work {therein}. {solemn...: Heb. restraint} Seven weeks shalt thou number unto thee: begin to number the seven weeks from {such time as} thou beginnest {to put} the sickle to the corn.