Metz was born on 5 August 1928 in Auerbach in der Oberpfalz and grew up there. As a teenager, Metz was drafted into the German military in 1944, towards the end of the Second World War. Six months before the end of the war, he was captured by the Americans and sent to prisoner of war camps in Maryland and then Virginia. After the war, he moved back to Germany. He studied theology and philosophy from 1948, first in Bamberg, then in Munich and at the University of Innsbruck, He completed his dissertation on the philosophy of Martin Heidegger in 1951. Metz was ordained a priest in 1954, working in ministry from 1958 to 1961. He was then promoted to Ph.D., with a work on the theology of Thomas Aquinas under the supervision of Karl Rahner. His experience in the war matches that of the German Calvinist theologian Jürgen Moltmann who would go on to write with Metz on political theology against a background of direct confrontation with Nazism. In 1962–63, he was granted a scholarship from the Deutsche Forschungsgemeinschaft.