Torah Portion: Tetzaveh
Upon [the Incense Altar] shall Aaron bring the spice incense (Shemos30:7).
It is a positive commandment upon the kohanim-priests to burn the ketores-incense twice a day on the Golden Altar, as it is written, Upon [the Golden Altar] shall Aaron bring the spice incense (Shemos 30:7). It is also a mitzvah upon them to prepare the incense for this purpose every single year. The preparation and the burning are reckoned as a single mitzvah.
Among the roots of this commandment is the aim of increasing the glory of the Temple and so that its status and respect should rest upon all people. It needs to be done this manner because it is impossible to impress people and their thoughts with anything but what they consider impressive. Now, it is known that a pleasant scent is something that people enjoy and it is very much appealing to the souls of people. The scent of the incense [in the Temple] was the most pleasant scent that could be produced by humans, to the point that our Sages said that it was possible to smell the incense from Jerusalem all the way to Jericho.
The laws of the mitzvah include: The ketores was comprised of eleven ingredients; four of which are mentioned explicitly in Scripture and the remaining seven are known through Rabbinic tradition. Its placement on the fire was performed either by the Kohen Gadol or by an ordinary kohen. Every day half a maneh was offered in the morning and another half in the afternoon, following the afternoon Daily Offering. If the incense was not burnt in the morning then the entire quantity of that day was burned in the afternoon.
At the time the incense was placed on the Altar no other person was present in the Heichal-Sanctuary nor between the Hall and the outer Altar. The incense was offered in this manner: the kohen would gently toss the incense on the coals that were on a golden pan; he would then bow down and exit.
This commandment applies when the Holy Temple stands, to kohanim.
