We read in Parshat Emor, Vayikra 23:10,14-15: “Speak to B’nei Yisrael and say to them ‘Ki tavou el Ha’Aretz- when you come into the Land that I give to you and you reap its harvest, you shall bring an Omer of the first fruits of your harvest to the Kohen…Bread, parched grain or tender grain you shall not eat until this very day, until you bring the offering of your God; it is an everlasting statute for all your generations (ledoroteichem) in all your dwelling places. You shall count for yourselves — from the morrow of the rest day, from the day when you bring the Omer of the waving- seven weeks, they shall be complete (temimot).’”
Before we eat any grain products of the new crop, an Omer (a dry measure containing the volume of 43.2 average eggs) of ground barley must be brought to the Beit HaMikdash (Temple) on the second day of Pesach. The Omer is a meal-offering that symbolizes the prosperity of the field. Although a tremendous amount of work is required, the crops are a gift of God that we must appreciate. Once the Omer is brought, we can eat all the grain that took root before that time. The later grain is only eaten after the following year’s Omer is brought. Since we don’t have the Beit HaMikdash today, we can eat the new crop after the second day of Pesach.
Rabbi Yochanan (Vayikra Rabba 28:6) taught: Do not take the mitzvah of the Omer lightly, for it was by merit of this commandment that Avraham was privileged to inherit the Land of Israel as it says in Breisheet 17:7-8 “I will ratify My covenant between Me and you and between your offspring after you, throughout their generations, as an everlasting covenant, to be a God to you and to your offspring after you. And I will give to you and your offspring the Land of your sojourns- the whole Land of C’naan — as an everlasting possession; and I shall be a God to them.” The Land was promised to you on condition that you keep my covenant as it says in the next two verses, Breisheet 17:9-10 “God said to Avraham, ‘And as for you, you shall keep (tishmor) My covenant- you and your offspring after you throughout their generations (ledorotam). This is my covenant which you shall keep (tishmeru) between Me and you and your descendants after you: Every male among you shall be circumcised.’” What is meant by covenant? The covenant is the mitzvah of the Omer.
The simple reading of the text teaches that the covenant is Brit Mila (circumcision), so where does Rabbi Yochanan get his idea that there is another mitzvah, another covenant alluded to that will give B’nai Yisrael the merit to enter and inherit the Land of Israel?
In reference to Brit Mila, God tells Avraham (Breishhet 17:1) “Walk before me and be perfect (tamim).” And in reference to the Omer it says (Vayikra 23:15) “seven weeks, they shall be complete (temimot).”
Concerning Brit Mila it says in Breisheet 17, “ledorotam”, “generations” and “throughout their generations” while it says in Vayikra 23:14 regarding the Omer: “ledoroteichem”, “for all your generations.”
Pertaining to Brit Mila it also says in Breisheet 17, “you shall keep” (tishmor, tishmeru) and we find in Yirmiyahu 5:24, “that keeps (yishamer) for us the appointed weeks of the harvest.” When we observe the Omer properly, God will make sure that the grain is in good shape for us.
The observance of the Omer is one of the Mitzvot HaTluyot Ba’Aretz, a mitzvah that is only observed in the Land of Israel so it was a new mitzvah for B’nai Yisrael when they arrived in the land with Yehoshua. They arrived at Pesach time and were able to cut down the produce of the land, bring the Omer and eat from the grain of the land immediately. They had already observed the mitzvot of Brit Milah and Pesach in Egypt as well as Pesach in the Sinai desert as they are mitzvot that are not only observed in Israel.
B’nai Yisrael’s swiftness in observing the Omer caused them to immediately inherit the Land of Israel. Through this mitzvah, they merited to complete God’s promise to Avraham that they would return to and inherit the land.