Tobias Theodores was born Theodore Tobias in Posen Province, Prussia in 1808. He entered business at an early stage, and moved to England, where worked in London and Manchester.
Although little is known of his early life, it appears that he spent periods teaching in Lancashire and Yorkshire. In 1851, Theodores was appointed tutor in German at the newly-opened Owens College in Manchester. In 1860, he was promoted to a chair in modern and oriental languages, which covered German, French, Hebrew and Arabic. In 1879, he relinquished the modern European languages part of this post. He retired from Owens College in 1884.
Theodores was best-known as a teacher, and succeeded in putting modern languages on a firm footing at Owens. His own capacity for learning new languages was considered phenomenal, and he is believed to have spoken at least several dozen different languages.
Theodores was a practising Jew, and closely associated with Reform Judaism, a movement which became increasingly prominent after 1850. Reform Judaism stressed, amongst other things, a diligent personal spirituality, a close reference to scriptural authority in matters of doctrine and law, and openness to non-Judaic religions and secular ideas.
Theodores wrote relatively few academic works. His best-known religious work was The Rabbinical law of excommunication published in 1854. He was however an active publicist for Judaism in the press, writing numerous articles for the Jewish Chronicle. In 1841, Theodores had come to public attention, writing a strong defence of the Jewish community in Damascus, which had been the subject of a blood libel. Theodores had been active in the establishment of the Manchester Congregation of British Jews in 1856, and was a close friend of its second rabbi, Gustav Gottheil (1827-1903).
Gottheil had moved to Manchester in 1860; previously he had been closely associated with advanced Jewish circles in Berlin. In 1873 Gottheil moved from Manchester to New York, eventually becoming rabbi at Temple Emanu-El in Manhattan, another Reform Jewish congregation. Theodores’ correspondence with Gottheil, after he left Manchester, forms the basis of this collection.
Theodores married Sarah Horsfall in 1839; they had one son, who predeceased them. He died at his home in Rumford St, Manchester on 27 April 1886.