This article seeks to examine how religious ideas that are not the focus of a particular halakhic question become the crux of the ruling, thereby molding it and dictating its bias. We will attempt to demonstrate this through a study of Jewish medical ethics, based on some of the rulings of one of the greatest halakhic decisors of the previous generation: Rabbi Eliezer Yehuda Waldenberg (1915–2006). Rabbi Waldenberg molds his rulings on the basis of a religious principle asserting that the (...) legitimacy of any medical procedure is qualified and limited. Rabbi Waldenberg rejects certain accepted medical practices, including plastic surgery, in vitro fertilization, and organ transplants. Even if these procedures are regarded by other halakhic decisors as being legitimate, for Rabbi Waldenberg they are ethically and religiously improper, and therefore they are halakhically forbidden. (shrink)