Wurm was active in politics. He was a member of the Christian Social Party before World War I, and thereafter of the Citizens’ Party. He held a seat in the Württemberg State Parliament (German: Landtag) until 1920.
As a young man Wurm was a prison chaplain, and became a parish pastor when he was 45. He progressed in the hierarchy of the Lutheran Evangelical State Church in Württemberg and became church president in 1929, with this office being retitled into Landesbischof (bishop of the regional Protestant church) in 1933. Like many churchmen, he initially favored the Nazi regime, but its church policy soon moved him into opposition.
In September 1934 Wurm was deposed from his bishopric by Reich's bishop Ludwig Müller because of his views on church policy (including) the Barmen Declaration, and was placed under house arrest twice. These extreme measures were eventually rescinded by Hitler in the wake of protests and the stripping of power from Müller. Wurm then held the office of bishop until 1948.
Wurm withdrew from the German Christians and aligned himself with the schismatic Confessing Church and attended its synods, but he did not advocate the more extreme policies of the church's more militant wing. Nevertheless, he was not politically apathetic and made numerous complaints to the Nazi party and the Nazi state. After the start of the war, he protested the murders of psychiatric patients under the Nazi euthanasia program. Wurm and the Catholic Bishop of Munster, August von Galen were able to lead widespread public opposition to the murder of invalids. This earned him a 1944 ban against public speaking and writing.
He was admired by his fellow churchmen and in 1945 (in connection with the Allies' de-nazification efforts) he was elected chairman of the Council of the newly created Protestant umbrella Evangelical Church in Germany.
He was a signatory of the October 1945 Stuttgart Declaration of Guilt.
- Peter Hoffmann; The History of the German Resistance 1933-1945; 3rd Edn (First English Edn); McDonald & Jane's; London; 1977; p.24
- Barnes, Kenneth C. (1991). Nazism, Liberalism, & Christianity: Protestant social thought in Germany & Great Britain, 1925-1937. University Press of Kentucky. ISBN 0-8131-1729-1 (''Barnes'').
- Barnett, Victoria (1992). For the Soul of the People: Protestant Protest Against Hitler. Oxford University Press US. ISBN 0-19-512118-X (''Barnett'').
- Hockenos, Matthew D. (2004). A Church Divided: German Protestants Confront the Nazi Past. Bloomington: Indiana University Press. ISBN 978-0-253-34448-9 (''Hockenos'').
- Online Biography of Wurm at German Resistance Memorial Center