See E. F. Miller, The Influence of Gesenius on Hebrew Lexicography (1927).
He was born at Nordhausen, Thuringia. In 1803 he became a student of philosophy and theology at the University of Helmstedt, where Heinrich Henke was his most influential teacher; but the latter part of his university course was taken at the Göttingen, where J.G. Eichhorn and T.C. Tychsen were then at the height of their popularity. In 1806, shortly after graduation, he became Repetent and Privatdozent at Göttingen; and, as he was later proud to say, had August Neander for his first pupil in Hebrew language. In 1810 he became professor extraordinarius in theology, and in 1811 ordinarius, at the University of Halle, where, in spite of many offers of high preferment elsewhere, he spent the rest of his life.
He taught for over thirty years, the only interruptions being that of 1813-1814 (occasioned by the War of Liberation, during which the university was closed) and those occasioned by two prolonged literary tours, first in 1820 to Paris, London and Oxford with his colleague Johann Karl Thilo (1794-1853) for the examination of rare oriental manuscripts, and in 1835 to England and the Netherlands in connection with his Phoenician studies. He became the most popular teacher of Hebrew and of Old Testament introduction and exegesis in Germany; during his later years his lectures were attended by nearly five hundred students. Among his pupils the most eminent were Peter von Bohlen, A.G. Hoffmann, Hermann Hupfeld, Emil Rödiger, J. F. Tuch, Wilhelm Vatke and Theodor Benfey.
In 1827, after declining an invitation to take Eichhorn's place at Göttingen, Gesenius was made a Consistorialrath; but, apart from the violent attacks to which he, along with his friend and colleague Julius Wegscheider, was in 1830 subjected by E.W. Hengstenberg and his party in the Evangelische Kirchenzeitung, on account of his rationalism, his life was uneventful. He died at Halle.
Gesenius takes much of the credit for having freed Semitic philology from the trammels of theological and religious prepossession, and for inaugurating the strictly scientific (and comparative) method which has since been so fruitful. As an exegete he exercised a powerful influence on theological investigation.
The first volume of his well-known commentary on Isaiah (Der Prophet Jesaia), with a translation, appeared in 1821; but the work was not completed until 1829. The Thesaurus philologico-criticus linguae Hebraicae et Chaldaicae V. T., begun in 1829, he did not live to complete; the latter part of the third volume is edited by E. Rödiger (1858). Other works include: De Pentateuchi Samaritana origine, indole, et auctoritate (1815), supplemented in 1822 and 1824 by the treatise De Samaritanorum theologia, and by an edition of Carmina Samaritana; Paläographische Studien über phönizische u. punische Schrift (1835), a pioneering work which he followed up in 1837 by his collection of Phoenician monuments (Scripturae linguaeque Phoeniciae monumenta quotquot supersunt); an Aramaic lexicon (1834-1839); and a treatise on the Himyaritic language written in conjunction with E. Rödiger in 1841.
Gesenius also contributed extensively to Ersch and Gruber's Encyclopädie, and enriched the German translation of J.L. Burckhardt's Travels in Syria and the Holy Land with valuable geographical notes. For many years he also edited the Halle Allgemeine Litteraturzeitung. A sketch of his life was published anonymously in 1843 (Gesenius: eine Erinnerung für seine Freunde), and another by H. Gesenius, Wilhelm Gesenius, am Erinnerungsblatt an den hundertjährigen Geburtstag, in 1886.