Huldrych Zwingli was born in January 1484, just six weeks after Luther. His life and ministry developed differently from Luther’s and some of the differences in context, education, and experience are factors in explaining the differences in their ministry and theology. Swiss patriotism influenced Zwingli as a boy, as Swiss humanism influenced him as a young man. His education in Vienna and Basel introduced him to scholasticism as well as to humanism, with the study of the writings of Peter Lombard, Thomas Aquinas, and Johannes Duns Scotus. The influence of the old way (via antiqua) contrasts with the influence on Luther of the modern way (via moderna). Zwingli was ordained in 1506 and served for a decade as priest in Glarus. His patriotism was expressed in his earliest surviving work, The Ox, an attack on Swiss mercenaries fighting for foreign powers. His experience of war as a chaplain deepened this opposition, especially the battle at Marignano (1515), in which thousands died fighting as mercenaries against the French. While at Glarus, Zwingli met Erasmus, who had a decisive impact on him. His crucial turning 'to Christ and to scripture' dates from this period. As a result, his reading shifted from the classics to the fathers, not least Augustine, and scripture.

After two years in Einsiedeln, a great centre of pilgrimage and Marian devotion, Zwingli was called to Zurich. His ministry there began on 1 January 1519 and lasted till his death in the battle of Kappel on 11 October 1531. In that period his influence went beyond Zurich to other cities in Switzerland and south Germany. His writings often reflect his engagement with supporters and opponents, especially conservatives and radicals in Zurich and Luther in Wittenberg. His early death meant that his theology was mediated in large part by others, especially Bullinger.