Louis Cappel (born October 15, 1585, Saint-Élier, France—died 1658) was a French Huguenot theologian and Hebrew scholar.
Cappel studied theology at Sedan and Saumur, both in France, and Arabic at the University of Oxford, where he spent two years in England. In 1613 he accepted the chair of Hebrew at Saumur, and in 1633 he became professor of theology there. Cappel’s important critical study of Scripture, Critica Sacra (1634), met with such theological opposition that he was not able to print it until 1650, at Paris, and then only with the aid of a son who had turned Roman Catholic. The various readings in the Old Testament text and the differences between the ancient versions and the Masoretic text convinced him that the integrity of the Hebrew text, as held by Protestants, was untenable. In particular, he showed that the Hebrew vowel marks could not have been part of the original texts. This amounted to an attack on the verbal inspiration of Scripture. Bitter as was the opposition, however, it was not long before his results were accepted by scholars.