Johann Leusden (16241699), Calvinist theologian and Hebraist. Having numbered Jews among his teachers, in 1650 he became a professor of Hebrew language at the University of Utrecht. In collaboration with the Amsterdam publisher Joseph Athias, he published the first Hebrew Bible in which the verses are numbered (Biblia Hebraica, 1661, 16672). The edition became well known for its exactness and beautiful print, and served as a model for almost all publications of the Bible up to the 19th century. Leusden was one of the foremost Bible scholars of his time and wrote several treatises on Bible research and Hebrew philology. He also translated (Utrecht, 1656) the catalog of 613 commandments that heads Maimonides' halakhic code.