Anabaptism was birthed amidst the ministry of Ulrich Zwingli and the Swiss Reformation in Zurich. The leading proponents of the movement were Felix Manz and Conrad Grebel, two of Zwingli’s disciples. 

Manz and Grebel claimed to carry Zwingli’s ideas of sola Scriptura to their logical conclusions. Their devotion to the authority of Scripture was admirable and essential but led them to embrace views that were considered shockingly unorthodox at the time. They called for the church to return to apostolic purity based upon scripture alone. It was imperative, in their minds, that all extra-biblical aspects of ecclesiastical governance be excised. 

They rejected infant baptism as unbiblical. This was a massive shift in thinking. Considering the high mortality rates prevalent in Europe, baptizing children immediately after birth was considered a sacred duty. If an infant died, as was often the case, their baptism would ensure them a place in heaven. Considering what Christendom believed about hell, purgatory, and anthropological dualism, this belief in infant baptism was essential for parental peace of mind. When Anabaptists renounced it they were considered not just sectarian but dangerously subversive. 

The Anabaptist understanding of baptism was scriptural. They believed that the biblical baptism, was for those who had repented, accepted Christ through faith, and had a clear understanding of the basic tenets of salvation and truth. They further pointed out that Sciprute only exemplifies adult baptism. There is no mention of infant baptism in Scripture. They based much of their understanding of Baptism on the theological pillar of Justification by Faith. 

It seemed logical to them that once an individual understood what they believed they were more likely to retain their faith. Infants couldn’t make an intelligent choice regarding salvation. However Anabaptist views of purity from sin led them to create isolated communities which were far removed from the world. 

Anabaptists believed that the original apostolic church was stripped of its purity when Emperor Constantine merged church and state to create the Roman Catholic Church in the 4th century. This led Anabaptists to reject many of the religio-political states of their day. Their convictions led them to evade tax, refuse military service, or become involved in politics. They were also pacifists. 

In general, early anabaptists such as Grebel and Mantz were critical of Luther, Zwingli and other reformers. They felt these men emphasized the importance of justification by faith alone at the expense of sanctification, which deals with the transformation of heart and life. 

Their unorthodox views made them the object of repeated persecution by many mainstream reformist denominations including, Lutherans and Zwinglians. It was Zwingli who first began to denounce Anabaptism. At a debate between Zwingli and the Anabaptists in 1525, the city council of Zurich condemned Anabaptism.