(b Stein, canton of St Gallen, 1 June 1924). Swiss hymnologist. He studied Protestant theology at the universities of Basle and Zürich with Karl Barth, Oscar Cullmann, Ina Lohr and Wolfram von den Steinen. He was successively rector of Saas, canton of Graubünden (1950–56), of Weinfelden, canton of Thurgau (1956–63) and of the Swiss Institute for Epileptics, Zürich (from 1963). In 1955 he took the doctorate with Ina Lohr at Basle with a dissertation on the Swiss Reformation hymnals of the 16th century. In 1964 he completed the Habilitation and became a lecturer in practical theology at the University of Zürich; he became professor there in 1973. He has prepared several editions of hymnbooks and was editor of Musik und Gottesdienst, 1975–83.
Jenny has confined himself almost entirely to questions of Protestant hymnology: his main works have been on the songs of the Zwinglian church and their links with and differences from those of the Lutheran church. In particular he has studied the function of church singing in Zwingli’s church and Zwingli’s own hymn writing.