The first point worth noting about this mitsvah is that Rambam counts it as de-oraita at all. Most rishonim, including Sefer haHinukh, who generally follows Rambam’s list, define this mitsvah as necessarily connected to the bringing of the Minchat haOmer at the time that the Beit haMikdash was still standing. According to them, the mitsvah is for each adult male Jew (this is, obviously, an example of a mitsvat `aseh she-hazman grama; to digress briefly, this is one of the strong proofs against the view that the Torah freed women from these mitsvot because they were too busy with other responsibilities—it takes three seconds to count the Omer, and even the busiest mother can do it if she wishes), to count daily from the event of bringing the Omer to the holiday of Shavuot.

Everyone agrees that the mitsvah is to count days as well as weeks, although there was an opinion in the gemara that we nowadays count only days, since our counting is only a memory of the Temple, rather than a fulfillment of a Torah commandment. When a mitsvah calls for counting both days and weeks, we should understand that there is a difference between the two experiences. Rambam, actually, felt the need to stress that these were only one mitsvah and not two, as if they were so distinct that we could have understood them as separate commandments.

To explain that difference, we would suggest that counting days does not necessarily involve appreciating the progression of those days (yesterday was 34, today 35, but nothing forces me to attend to the whole that those days combine to make). When the element of weeks is added, though, those days are necessarily put in the context of the whole that is being made. The opinion that we do not count weeks when the mitsvah is de-rabanan might be assuming that we nowadays do not count from or towards anything, but just count as a reminder of the Temple.

To the extent that the mitsvah fundamentally only related to the actual bringing of the Omer, it interests us less here since it is not essential to Jewish observance, only to the ideal form of Judaism available to those blessed to live in the times of the Temple. To offer a brief thought on the matter, the obligation seems to suggest that the Torah wanted the citizenry in general to pay attention to these events in the Mikdash, rather than having them just happen for the actively involved elite. The obligation to count was a way to insure that ordinary Jews would also be aware of and affected by the progression being lived out in the Mikdash.

That progression might affect us here as well, even though we only note this mitsvah since Rambam viewed it as de-oraita even in our times. As a de-oraita, the mitsvah must be somewhat independent of the bringing of the Omer. An extreme version of that independence was the Hinukh’s explanation that the mitsvah stresses the importance of connecting our freedom from Egypt to the receiving of the Torah. In that reading—and it is odd for the Hinukh to offer it, since he agrees with the majority view, that it is only de-oraita in the presence of an actual Omer—the counting is more about bridging the gap between the two holidays than about the Omer experience at all.

It seems possible to offer an explanation for the timelessness of the mitsvah that yet maintains a clearer connection to the Omer. Remember that, in the time of the Temple, any grain planted after the previous year’s Omer was brought was prohibited for use until the offering of the Omer. The Omer, however, affected only grain used outside of the Temple. The Temple itself did not use new grain until Shavuot, when the shetei halehem, the two loaves of bread, were brought. Shavuot, then, was a sort of Rosh haShanah for the Temple, since it was the time when a new set of produce became acceptable.

That sequence, it seems, might be universally applicable, and one that Jews were meant to recognize in all times and places. Many mitsvot send the message that we do not use this world and its blessings until we give some to God. The mitsvah of counting the Omer shows us that the ordinary and the sanctified should be dealt with separately, although connectedly, in this regard. Even after we have renewed our appreciation of the grain God gives us in ordinary terms, we need to work our way up to that new harvest in sanctity terms. Attending to that process of working carefully from the mundane to the sacred, of the need for extra preparation before we are ready to usher in a new holiness year, as it were, might be the message of this counting on a regular basis.