Swiss Reformer (1484-1531), leader of the Reformation in Zürich, and (alongside Luther) one of the two chief first-generation Protestant reformers. A Catholic priest educated in humanism (he corresponded with Erasmus), Zwingli came to evangelical convictions independently of Luther, beginning around 1516. Appointed preacher at the Grossmünster in Zürich in 1519, he systematically preached through Matthew, Acts, the Epistles, and on from the Greek text — modeling what would become classic Reformed lectio continua preaching. The Zürich City Council, convinced by his biblical arguments at public disputations in 1523 and 1525, formally broke with Rome.
Zwingli's trademark contributions: (1) Regulative principle of worship — the Church may include in worship only what Scripture commands; not, as Luther held, whatever Scripture does not forbid. This principle stripped Reformed worship of images, relics, chant, and the Mass; (2) Memorial view of the Lord's Supper — the elements signify Christ's body and blood but do not convey any "real presence" beyond spiritual communion in faith. Zwingli and Luther famously failed to reconcile at the Marburg Colloquy of 1529 specifically over this question — a split that divides Lutheran from Reformed to this day; (3) Total rejection of the Mass as re-sacrifice and of priestly mediation. Zwingli also spawned a debate with the early Anabaptists (who pushed further than he was willing to go on baptism and civil magistracy) that ended, tragically, in their persecution. Zwingli died in battle at Kappel in 1531, serving as military chaplain when Catholic forces overran the Zürich camp. The Reformation in German-speaking Switzerland was continued and consolidated by Heinrich Bullinger, Zwingli's successor.