Avodah Zarah 52 - A Bath with an Idol
If a bath was built for or dedicated to an idol, it does not enhance the beauty of the idol, nor does the idol enhance the bath. Rather, the profits from the bath go to support the priest of the idol. Can one benefit from the bath which is the property of the idol? Since idol cannot own property, the rule is that "there is no consecration of property to an idol," and the bath is allowed to be used. However, one is not allowed to pay the priest, since his payment goes to their support. Some opine that one is allowed to pay but not to express gratitude to the priests - so that one does not come to be influenced by them.
An idol of a non-Jewish idol worshipper becomes prohibited immediately after he forms it, but that of Jewish idol worshipper - only after it is worshipped. However, Rabbi Ishmael gets an opposite result from the phrase, "You shall destroy the places where the nations worshipped their gods," - which according to him means that they becomes gods only after being worshipped.
Art: Hubert Robert - Ancient Ruins Used as Public Baths