Zeller believed that education was the main method to get to the heart of the people and to increase the Protestant influence in Nazareth and the area. This was not easy, since there was great pressure on those people who sent their children to the Protestant school. However, Zeller persevered to establish and develop the school, believing that it would be the seed for the Anglican denomination. Furthermore, he did not stop in Nazareth, but opened classes in Reineh, Kafr Kanna and Jaffa of Nazareth (Yafa an-Naseriyye), and later on in Shefa-'Amr. In the early 1870s he rented a room in Acre and started classes there. He also assisted his Armenian colleague Kaloost Vartan of the Edinburgh Medical Missionary Society in the founding of the Nazareth Hospital.
