פירוש על עבודה זרה 41:5

In Syria, the region outside of Israel, the rules are slightly more lenient, but it is still prohibited to sell them houses. In principle, this should be permitted because this is not the land of Israel. But it is prohibited lest someone come to sell them houses in Israel itself. But the prohibition does not extend to letting them houses, because the prohibition of renting a house in Israel is itself only a safeguard against selling them houses. There is a principle that we do not make a decree not to do something lest someone do something else that is only prohibited by a decree and not by a principle.