This study proposes a brief reflection on the problematic of the report between the human reason and the faith in the fulfillment of the man. On one hand, it raises the voice of some modern thinkers who presume an exclusivity of the reason, and on the other hand, it emerges the claiming of certain believers who postulate an exclusivity of the faith. But both some and the others converge to assert an incompatibility between reason and faith. However, our approach consists exactly in putting forward some biblical and patristic arguments in favor of their plenary compatibility. The authentic vocation of the reason is to support the relation of the man with God, and it is in this purpose that it always needs to be strengthened and accompanied by the faith, the only force capable of helping it to develop and reach so its real goal.