This article is about life of Vladimir Petržek, student and Saint, on the occasion of the 100th anniversary of the Orthodox Theological Faculty of the University of Belgrade. Article is about the historical context of theology and pan-Orthodox cooperation in the 20th century, the relations between the Serbian Orthodox Church and Orthodox Churches in the Czech Republic and Slovakian countries, but also to explain the true faith and life in the Church in the turbulent 20th century, and also to describe the life of a Czechoslovak student, later a priest-martyr in the Second World War, Vladimir Petržek. He began his student days in Belgrade (1928–1932), and then the article developed through an analysis of Vladimir’s theological works published in the journal Svetosavlje and shows that theology is in fact the life of an Orthodox clergyman and that through his theological contribution shows both his life and his zealous confession of God through an experienced and active faith. Precisely this complementary examination of true faith in God and active faith in the life of a priest in the 20th century, the century of many martyrs, is the goal of this research.