⭐ Less than ten years after Luther's death, the very question he considered most representative of his whole life's teaching split open inside his own camp — and both sides were Luther's men.
The issue
In conversion, does the human will cooperate with God?
Claim
The Philippists (Melanchthon's line): in 1555 Johann Pfeffinger published his Propositions on Free Will, repeating Melanchthon's three-cause formula — the Word, the Holy Spirit, the will. He also argued that the fact that some respond to the call of faith and others do not is due to the freedom of the will. In 1560 Viktorin Strigel argued along similar lines in a public debate with Flacius.
Counterclaim
The Gnesio-Lutherans, led by Nikolaus von Amsdorf and Flacius. ⚠ But Flacius pushed too far in this debate — he held that original sin is not an accident but the very essence of fallen human existence, and that what we have is no longer the image of God but the image of Satan. As a result, González reports, his own side judged that he had come close to Manichaeism; he lost his place as their spokesman, went into exile, and died far from home in a Catholic convent.
Aftermath
⚠ The point at issue, González notes, remained unresolved and went on dividing the Philippists and the Gnesio-Lutherans, until the Formula of Concord gave an answer in 1577. ⭐ What we want readers to see here is this: the divide between synergism and monergism is not a divide of Catholic versus Protestant. As soon as it entered Protestantism it was played out all over again — and between Luther's closest co-worker and his most loyal disciples.