The Mishnah and Talmud have defined idolatry. It includes worshiping an idol in the manner of its worshipers. This is called ″customary worship″. Another criterion is worshiping the idol with acts which are for worshiping God in the Temple. These include animal sacrifice, incense burning and sprinkling blood. Performing one of these acts means the performer is dubbed an idolater. The third criterion of idolatry is prostration. This includes bowing down with at least the head or knees on the ground. Acts such as kissing, embracing and honoring are forbidden but are not considered to come under idolatry. The performer of such an act does not receive capital punishment unlike the idolater in Jewish law. Tractate "Avodah Zarah" of the Talmud governs Jewish interactions with idolaters. It places certain restrictions on business dealings with idolaters for the days in proximity to idolatrous festivals. It was forbidden to provide or take any benefit from idolatrous actions. These regulations had a strong impact on Jewish business dealings with Christians during the Middle Ages. Because Jews regarded Christians as idolaters because of Christian doctrines such as the trinity, Jews would not do business dealings with Christians on Sundays. Business dealings with Muslims were not affected because Jews regarded the Muslims as pure monotheists like themselves.