This holiday is also known as Chag HaBikurim (“The Festival of the First Fruits”).
וּבְיוֹם הַבִּכּוּרִים בְּהַקְרִיבְכֶם מִנְחָה חֲדָשָׁה לַה’ בְּשָׁבֻעֹתֵיכֶם מִקְרָא־קֹדֶשׁ יִהְיֶה לָכֶם כָּל־מְלֶאכֶת עֲבֹדָה לֹא תַעֲשׂוּ׃
On the Day of the First Fruits, your Holiday of Weeks, when you bring an offering of new grain to the Lo-rd, you shall observe a sacred occasion: you shall not work at your occupation:.
Bamidbar 28:26
Shavuot as one of the Shalosh Regalim (“Three Pilgrimage Holidays”) would be a time where Jews from all over Israel would gather at the Temple in Jerusalem and offer the first fruits of their harvest. The Bikkurim, or First Fruits, were of the seven species of the Land of Israel; wheat, barley, grape, fig, pomegranate, olive (oil), and date (honey).
Devarim 8:8