We are in the middle of sefirat ha-omer, the daily counting of the 49 days between pessach and shavuot. This mitzvah appears in this week's parasha and the midrash says that we should not consider the omer as a "light mitzvah" because Avraham received the promise about inheriting the land of Israel based on this mitzvah. This requires an explanation; what is so special about the sacrifice of the omer that by fulfilling it Avraham received the Promised Land?
Another midrash may offer us an explanation. R. Yanai says that a man buys a piece of meat in the market and then goes through great pains to make that piece of meat get to his plate as food. On the other hand, while that same man is asleep in bed, God makes the winds blow, the clouds form and the plants and fruit grow. And the only compensation God receives for all this is the omer sacrifice, which is brought to the cohen. So according to this midrash, we "pay God back" for everything he does for us by fulfilling the mitzvah of the omer.
The Maharal explains this midrash as follows: God governs the world using both open, visible miracles and secret, unexposed miracles. When we are worthy enough to experience a visible miracle - such as the parting of the Red Sea or the halting of the sun in Joshua's days - our faith in God is absolute. After all, it is difficult not to believe when you witness God's deeds first hand. However, it is much harder to have faith by observing nature, which is in effect God's way of governing the world using hidden miracles, miracles which we do not perceive as being miraculous. As the Ramban teaches us, the essence of faith is tested in the belief in this "hidden hand". The omer sacrifice epitomises the presence of God in nature, such as it is described in the above midrash (clouds, winds, plants, trees). But is man able to pay attention to all these miracles while "sleeping in bed" and thank God for them?
This is where the omer comes in. It is an offering based on the product of nature and by fulfilling this mitzvah man becomes aware of the hidden miracles God performs through nature and his indebtedness to God. He thanks God by offering this sacrifice to the cohen and this thanking is the "payment" we offer God for what he does for us.
So now we can close the loop and understand how the omer and the promise of the Land of Israel to Avraham are connected. When the people of Israel were in the desert they lived by open and visible miracles: the manna from heaven, the fact their clothes remained in perfect condition for 40 years, the clouds that protected them, etc. But after they entered the Land of Israel all of these visible miracles stopped and the laws of nature - the "hidden miracles" - took over. Keeping the faith was much harder now, so the keeping of the mitzvah of the omer - a sacrifice brought from nature - symbolised that the people of Israel continued to believe in God even in this new situation. He who is able to thank God for the miracles of nature is the one that deserves the promise of the Land of Israel.
The idea for this week's Torah thought is from R. Zechariah Tubi.