After his own study of the scriptures, the church fathers, and the writings of Martin Luther, Bullinger fully embraced the principles of the Reformation.

After a short period of time in the ministry he distinguished himself as a preacher and theologian. He then followed Zwingli as the pastor of the church in Zurich.

Bullinger played a central role in creating in the writing of the First and Second Helvetic Confession. His most known work “The Decades” had a major impact on the English reformation.