149. Stone Floors in Shuls
Avodas Kochavim 6:7
The prohibition against bowing down on a stone applies everywhere outside the Temple. In the Temple, one may bow down to God on a stone surface. This is derived from Leviticus, 26:1, which says, “Do not place a kneeling-stone in your land.” It is only prohibited to bow down on stones “in your land.” It is permitted to bow down on the stone floors of the Temple.
Because of this prohibition, the universal practice is for Jews to place mats on the floors of shuls that are paved with stone in order to separate them from the stones. If there is nothing one can use to separate between himself and the stones, he should move elsewhere to prostrate. Otherwise, he can lie on his side so that he will not place his face to the stone.
Avodas Kochavim 6:8
If a person prostrates himself to God on paved stones but he does not spread out his hands and feet, he is not liable to the penalty of lashes. He is, however, punished by stripes for acting rebelliously. Conversely, one who bows down to an idol is liable to death by stoning whether or not he spreads out his hands and feet. In such a case, one becomes liable as soon as his face touches the ground.