FORT WORTH, Texas (SWBTS) – As a professor at the University of Wittenberg, Germany, Martin Luther nailed what is now commonly called his 95 theses—written against the Catholic tradition of indulgences—on the door of Castle Church on October 31, 1517.

Craig Blaising, executive vice president for Southwestern Seminary and speaker for a chapel service in honor of Reformation Day, said this incident was of utmost significance to the Reformers.

“It was that incident in 1517 that seemed to be used by God to pull the elements together that would become the Reformation,” he said. “[The] issue of course that was so important to us was the clarification of the Gospel and also, the recovery of the sole authority of Scripture.”

Despite forming a clear split with Catholicism as subsequent Reformers took up the cause of Luther, Blaising said a movement, starting in the 1980s, to reunite Catholics and evangelicals, led some, mistakenly, to the conclusion that to return to their ‘Catholic roots’ is a logical choice.

However, to equate Roman Catholicism with protestant Christianity is to disregard essentials of Catholic belief, he challenged. These included the belief of authoritative church tradition, the practice of the sacraments and the elevation of Mary as a “co-mediator and ‘close’ mediator” between God and Christians.

“All of this basically renders a completely different understanding of salvation,” said Blaising. “That’s why the Reformation took place, to recover the Gospel in its purity and to recall the sole authority of God’s Word.”

A full recording of Blaising’s chapel message can be found at