When Hashem created the heavens and the earth, He created time as well.
Chazal say that every thing has its place, but every man has his hour (Avos 4:3). We live in the physical world, in space; but so do other creatures. The consciousness of time is unique to man; thus he is associated with time rather than space.
Yet, though he perceives it, he does not possess it. Time is compared to a river, which constantly flows. Yet even a great river can be controlled; it can be diverted or dammed. But the flow of time is unalterable.
All that we can do is to note its passage, to measure it. With increasingly more sophisticated instruments — sundials, water clocks, mechanical clocks, digital and atomic clocks — our ability to quantify time has become ever more precise. We have divided it into seconds, into fractions of seconds, into picoseconds. But all this measurement has afforded no greater power over it.
Except insofar as the Jew is concerned. For the Jew does not merely mark time, he sanctifies it. By observing Shabbos, by proclaiming Rosh Chodesh and the chagim, we bear witness to the creation of the world and events that have occurred in, but transcend, time. We recognize the Creator of time, Who transcends time.
There is one mitzvah that relates to time more directly, more exclusively, than others: Sefiras HaOmer. The mitzvah is to count days — that and nothing more — with no Kiddush, festive meal, korban, lulav or shofar. There is nothing more to it than the awareness of time through counting.
The meforshim ask what was the necessity for the miracle that no pesul, no disqualification, was ever found in the Korban Omer (Avos 5:5). While it is true that if the Omer, the barley offering, were disqualified, the new grain would be forbidden; but the law permits additional barley to be cut during the day if what was cut the previous night is unusable. (The mitzvah was to cut it on the night of the 16th of Nissan).
However, because Jewish communities distant from the Beis Hamikdash relied on the alacrity of the Kohanim to bring the Omer by midday of the 16th, they would assume that it had been brought, even before receiving official confirmation from the Sanhedrin. If there was a disqualification, the delay would likely be significant.
Due to the elaborate preparation, the grinding and sifting of the flour, only a small quantity, just sufficient for the morning’s offering, was normally cut. If that was unacceptable, the process would have to be repeated, and it took time to carry it to the Mikdash as well.
Yidden in communities distant from the Beis Hamikdash would not know about it until it was too late and they had already eaten from the as-yet prohibited new grain. (Rashi, Midrash Shmuel).
To protect them from such a transgression, albeit unintentional, Hashem saw to it that the Omer was always acceptable and no delay occurred.
The teaching here is that just as min haShamayim an unrectifiable transgression (me’uvas lo yuchal liskon) was not allowed to happen, so too we should take all possible precautions to ensure that such a thing not occur. If an opportunity to perform a mitzvah comes to hand, waste no time or effort in performing it, lest some problem arise and the opportunity pass. (Me’am Loez, Avos)
(Eis laasos laHashem, hefeiru Torasecha — time to do for Hashem, violate Your Torah — has been interpreted to refer to those people who are inclined to put off doing mitzvos, saying, “Well, there’s still plenty of time to do for Hashem,” and then the mitzvah is gone — violating Your Torah).
During Sefirah, we count the days to Shavuos, to Mattan Torah, not only to express our eagerness for Torah, but to impress upon ourselves the value of each day and each moment, to learn Torah and to work on ourselves, to prepare for receiving the Torah. At Yetzias Mitzrayim we were elevated by Divine chessed from the 49th and penultimate level of impurity to a most lofty level of spirituality. Hashem Himself, not a malach, slew the firstborn Egyptians and delivered the Jewish people from bondage.
But that high level of sprituality was transient. From then on, it was the task of Bnei Yisrael to attain heights of ruchniyus through their own efforts.
The seven weeks from the 16th of Nissan to Maamad Har Sinai was a time of preparation. Each day was an opportunity for Bnei Yisrael to work on themselves that would never come again, a window in time that would never again open.
That is what we must try to learn from Sefirah: the supreme value of time and its evanescence. For we are creatures of time, not masters of it.