Summa Theologica, Volume 5 (Part III, Second Section & Supplement)

Renowned for its theological depth, this work by Saint Thomas Aquinas serves as a comprehensive summary of Catholic doctrine and philosophy. It has been pivotal in shaping Church teachings and is frequently referenced for religious inquiries, particularly during significant events like the Council of Trent. Aquinas's insights and arguments have solidified his legacy as one of the most influential theologians in Catholic history.