The 12th prohibition is that we are forbidden from making stones which are prepared1 to bow down upon — even if this bowing down is to G‑d, exalted be He. The reason for this prohibition is also2 to not resemble that of idolatry, since they would place stones decorated by expert craftsmen3 in front of the idols, and bow down upon them to that idol.
The source of this commandment is G‑d's statement (exalted be He),4 "Do not place a designed5 stone in your land so you can prostrate yourselves on it."
One who transgresses this prohibition is punished by lashes.6
In the words of the Sifra,7 "The phrase, 'Do not place [a designed stone] in your land,' teaches that only 'in [the rest of] your land' you may not bow down upon stones; but you may bow down upon stones in the Holy Temple."
The details of this mitzvah have been explained in the Talmudic tractate Megillah.8
