Eyewitnesses to Zwingli’s sermons were always incredibly impressed. For instance-
Caspar Hedio, subsequently the Reformer of Strassburg, who wrote from Basel to Zwingli on November 6, 1519 (vii., 89), in the following very complimentary terms respecting a sermon he heard him preach at Einsiedeln at Pentecost, apparently of that year, 1519, from Luke, 5:17–26, the story of the paralytic:
“I was greatly charmed by an address of yours, so elegant, learned, and weighty, fluent, discerning, and evangelical, such a one as plainly recalled the energy of the old theologians.… That address, I say, so inflamed me that I began at once to feel a deep affection for Zwingli, to respect and admire him.”*
Other hearers also gushed compliments. There’s little doubt that Zwingli’s success as a Reformer was in no small part based in his success as a brilliant preacher. The best, I suspect, of all the Reformers (since no one seems to have felt as strongly about either Luther’s preaching or Calvin’s).
*Samuel Macauley Jackson, Huldreich Zwingli: The Reformer of German Switzerland (1484–1531), Heroes of the Reformation (New York; London: G. P. Putnam’s Sons; Knickerbocker Press, 1901).