The second head of the Solitary Brethren of the Community of the Seventh Day Baptists at Ephrata.
Entered the University of Heidelberg (1725). In 1730, he emigrated to Pennsylvania, was ordained by the Presbytery of Philadelphia, and began preaching to German Reformed congregations on the frontier. He soon became a disciple of Johann Conrad Beissel, a journeyman baker turned evangelist, who founded the Community at Ephrata.
Reputed to be one of the most learned of the Pennsylvania clergy, he shocked the province when in 1735, he publicly renounced the Reformed Church and was rebaptized by triple immersion. Lived as a hermit (May-November 1735) before joining Beissel and his followers at Ephrata. Miller, also called Brother Jabez, was the only member of the Ephrata community who corresponded with Franklin. Upon Beissel’s death, he succeeded him as leader of the Community.
Edited various books issued on the cloister press. In 1748, he translated J. T. V. Braght’s work on Mennonite martyrs from Dutch into German: Der Blütige Schau-Platz oder Martyrer Spiegel. Engaged by the Continental Congress to translate the Declaration of Independence into several European languages.
Born in Germany, probably at Zweikirchen, near Zweibrücken.