Ricardo da COSTA and Armando Alexandre dos SANTOS

Original title: O pensamento de Santo Tomás de Aquino (1225-1274) sobre a vida militar, a guerra justa e as ordens militares de cavalaria

Published in The Middle Ages and the Crusades

Keywords: Crusades, Military life, Religious life, chivalry.

The article briefly presents the thought of Thomas Aquinas about the legitimacy of military life and the concept of just war, and its theological justification in the context of the Crusades, to the military orders. For that, initially uses the Biblical foundation. The following briefly lists some of the saints of the Church, to discuss the thought of Aquinas about the subject.