Torah Portion: Tzav
“אש תמיד תוקד על המזבח…” (ויקרא ו ה)
It is a positive commandment to kindle fire on the Altar every day, continually, as it is written, A continual fire on the Altar shall be kept burning on it (Vayikra 6:5). The meaning of “continual” is that it is necessary to place wood on the Altar in the morning and in the afternoon. And even though the fire would come down from Heaven, it was nevertheless a mitzvah to also bring ordinary fire. And although in any case it was necessary to have a fire for burning the offerings, there was a mitzvah to have a fire burning separately, in addition to the fire of the offerings.
Among the roots of the mitzvah is the idea that even when Hashem performs miracles, He always brings them about it a hidden manner, so that the appear somewhat natural. For instance, even at the miracle of the Splitting of the Yam Suf, it is written, and Hashem moved the sea with a strong east wind all the night, and He turned the sea to damp land and the water split (Shemos 14:21). Those who possess [Divine] insight understand that the reason for this hidden manner is due to the exaltedness of the Master and the inferiority of the recipient [i.e., humans]. Hashem therefore commanded to kindle a fire on then Altar despite the fact that there was fire that came from Heaven, in order to conceal the miracle.
The reason why there was a mitzvah to light a fire on the Altar in addition to the fire that was needed for the offerings, is that since a person is blessed in accord with his deeds that he does for the will of his Creator — such as the blessing that comes upon every mundane bread [as reward] for our involvement with the mitzvah of holy bread [i.e., the mitzvah of separating challah] — so too the daily involvement in the mitzvah of the fire brings about blessing in the fire that is within man, which is the nature that is within him. For through that “fire” the person is strengthened, animated and active; therefore, it requires extra blessing. And since the idea of “blessing” is perfection, that is, something that is neither deficient nor redundant, so, too, the fire that is within man requires this blessing so that he has just the right amount of it that he needs.
This mitzvah applies when the Holy Temple stands, to the males of the kohanim. If the kohanim failed to kindle this separate fire on the Altar, they violated this positive commandment.