Written by: Ted Vial
The reformers immediately faced challenges. Having argued that scripture is the ultimate authority in matters of belief and practice, elevating it over human institutions (like the papacy), the reformers trusted that the same Holy Spirit who created scripture would lead the elect (saved Christians) to a correct interpretation of scripture. The Roman Catholic Church predicted that without institutional authority, people would not properly interpret the scripture and would not agree on what scripture meant, the result being schism and anarchy. On the latter count the Catholics turned out to be largely correct.
At the Second Zurich Disputation in October 1523 the City Council agreed with Zwingli that the Mass (the Roman Catholic celebration of the Lord's Supper, which is framed as a recapitulation of Jesus' sacrifice performed by priests as an offering to God) should be abolished, and that the use of images in worship was not scriptural. Zwingli was an astute enough pastor to understand that too rapid a change in ritual practice would upset rather than reassure his parishioners and would work against the ongoing process of reformation. He was content to allow the City Council to set the schedule of changes in the Lord's Supper.
Zwingli was immediately opposed by a group of people more radical than he, who labeled him a "half-way man." Conrad Grebel (ca. 1498-1546), George Blaurock (1491-1529), and Andreas von Carlstadt (ca. 1480-1541), who earlier had hailed Zwingli as a hero, now turned on him. They argued that the Holy Spirit had already abolished the Mass, and it would be against God's will to leave the slower pace of reform in the hands of the City Council. They also argued that correct performance of the Lord's Supper required strict adherence to the description found in the New Testament, down to details such as using unleavened bread. (Zwingli argued that certain key beliefs such as justification by faith were non-negotiable, but other matters such as type of bread to be used in the Lord's Supper could be left to the choice of individual congregations.)
Further, they argued that since justification was by faith, only those old enough to understand sin and redemption could be baptized. They therefore rejected infant baptism. Believing that their own infant baptisms were not valid, they baptized each other. For this reason their opponents labeled them Anabaptists (that is, "re-baptizers"). Zwingli had maintained the practice of infant baptism with, he felt, good theological and scriptural warrants. Theologically, Zwingli believed that infant baptism was a sign that salvation was entirely God's work, with no human activity required or possible. Scripturally, Zwingli held that baptism functioned for Christians the way circumcision functioned for the Israelites (who circumcised their boys eight days after birth). He also relied on a New Testament passage (Matthew 19:14) in which Jesus contradicted his disciples and let children gather around him.