He was a Lutheran pastor, born in Saxony in 1834. He studied Lutheran theology in Vienna, Göttingen and Berlin, and was awarded his PhD in 1856 from the University of Rostock. He became a pastor in 1859 in Bielsko, in 1866 an elder of the Silesian Lutheran Board of Elders, then in 1882 the pastor of the Cieszyn Lutheran Community. He founded many Lutheran schools, associations and charitable institutions, published several journals (some in Polish), and worked as an academic. In the years 1870-1876 he was a member of the Town Council in Bielsko, and a deputy in the National Council from 1873. He was also a representative in Silesian and Austrian institutions in later years. His most important achievement in Cieszyn was the foundation of the Lutheran general hospital which was opened on 14 July 1892. Haase collected funds towards the opening of the hospital with a wide-ranging campaign of talks and lectures throughout the whole monarchy, and even in the United States. He received a medal and an honorary diploma at the World’s Fair in Chicago in 1893 for his contribution to the founding of the Cieszyn hospital.
       Some time before, on 18 January 1893, a group of 22 Cieszyn councillors submitted a written proposal to honour Haase (and Franz Illich at the same time) with the title of honorary citizen of Cieszyn. The proposal was presented at a meeting of the Town Council on 30 January 1893 and passed unanimously. The work of Haase in connection with the opening of the hospital was the main grounds for the award. On the following day Mayor Dr Leonhard Demel informed Haase about the honour by telegram. Apart from honorary citizenship of Cieszyn, Theodor Haase received the same titles from both Bielsko (1876) and Strumień (1894). He died in 1909. A bust in honour of Haase was unveiled in the Silesian Hospital in Cieszyn in 1912.