In religion and ethics, inviolability or sanctity of life is a principle of implied protection regarding aspects of sentient life which are said to be holy, sacred, or otherwise of such value that they are not to be violated. This can be applied to both animals and humans, for instance in religions that practice Ahimsa, as both are seen as holy and worthy of life.
The concept of inviolability is an important tie between the ethics of religion and the ethics of law, as each seeks justification for its principles as based on both purity and natural concept, as well as in universality of application.
The phrase sanctity of life refers to the idea that human life is sacred and holy and precious, argued mainly by the pro-life side in political and moral debates over such controversial issues as abortion, contraception, euthanasia, embryonic stem-cell research, and the "right to die" in the United States, Canada, United Kingdom and other English-speaking countries. (Comparable phrases are also used in other languages.) Although the phrase was used primarily in the 19th century in Protestant discourse, after World War II the phrase has been used in Catholic moral theology and, following Roe v. Wade, Evangelical Christian moral rhetoric.