S. Jackson remarks, justifiably,
On April 14, 1525, Zwingli was chosen rector of the Carolinum, the Great Minster school; consequently he moved into the official residence of the rector, and lived there until death. He used his new position to improve the schools and took part himself in the biblical instruction, which he had made part of the curriculum. That he was still fond of humanistic studies and had not forgotten his Greek amid all his absorbing labours, he demonstrated by issuing on February 24, 1526, in Basel, an edition of the poems of Pindar.
Zu den schönsten Zeugnissen von Zwingiis Verehrung der Antike gehört seine Praefatio und seine Epistola zu der Pindar-Ausgabe seines früh verstorbenen Freundes Jakob Ceporin. Ihre Bedeutung ist daher auch in der neuen Zwingliausgabe (Bd. IV, S. 863 ff.) entsprechend hervorgehoben worden.
You can read the Preface here. Zwingli was a man of learning. And he remained exactly that his entire life.