After his mother died early in his childhood, his father married Johanna Deel and the family moved to The Hague where Theodor attended Latin school.

In 1821 he enrolled in theology and Semitic languages at the University of Leiden under Hendrik Arent Hamaker (1789–1835) and Johannes Hendricus van der Palm.

[n 2][1] In 1828, he entered the parish ministry of Voorhout, where he worked as a pastor until 1831 when he succeeded Groenewoud as professor of semitic languages at the Athenaeum in Franeker.

He taught Hebrew and Semitic languages and Jewish antiquities and later the Old Testament and Arab writers.

[2] In the same year he received a royal honor as a professor of Oriental languages and Hebrew history at the University of Groningen.