He prohibited us from making a vapor with the configuration of the [Temple] incense - meaning that it be from those spices and proportionate to its measurements - and have the intention to vaporize it. And that is His, may He be exalted, saying, "according to the composition of it, you shall not make it for yourselves" (Exodus 30:37). And it is explained that anyone who transgresses and makes its likeness, to smell it, is liable for excision - His saying, "Whoever makes any like it, to smell of it, shall be excised" (Exodus 30:38) - if he was volitional; and if he was inadvertent, he is liable for a fixed sin-offering. (See Parashat Ki Tissa; Mishneh Torah, Vessels of the Sanctuary and Those who Serve Therein 2.)