Who is described as one who acts without moral restraint and defies religious precepts?

The term that best describes someone who acts without moral restraint and defies religious precepts is "libertine." A libertine is typically characterized by a lifestyle that rejects accepted standards of morality, especially in relation to sexual behavior. This term suggests not just a lack of restraint but often implies a conscious choice to live in contradiction to societal or religious norms.

While "licentious" could also relate to a lack of restraint, particularly regarding sexual freedom, it doesn't necessarily encompass the broader implications of defying moral or religious standards that come with being a libertine. "Indulgent" describes someone who gives in to their desires, but it doesn't specifically imply defiance against morality or religion. "Infallible" refers to the inability to make mistakes or be wrong, which is unrelated to moral behavior.

Thus, "libertine" captures the essence of acting without moral restraint in the context of defying religious precepts most accurately.