Revelation 20:7-10
7 Now when the thousand years have expired, Satan will be released from his prison 8 and will go out to deceive the nations which are in the four corners of the earth, Gog and Magog, to gather them together to battle, whose number is as the sand of the sea. 9 They went up on the breadth of the earth and surrounded the camp of the saints and the beloved city. And FIRE came down from God out of heaven and devoured them.
NKJV
The "FIRE which came down from God out of heaven" was, once again, the Holy Spirit Himself as He moved through "the Reformers" whose ministry is commonly known as, "The fires of the Reformation" or simply, "Reformation fire." This Holy Ghost fire was the great rescue of true Christendom (Augustine's "City of God") which had become besieged by enemies on every side: militant physical enemies, (resurgent Islamists and atheists and the Golden Hordes of the Far East, et al), as well as ravenous ecclesiastical enemies (religious dictatorships of institutionalized heresy in high ecclesiastical office).
These Reformers, armed within by the Word of God and powered by the Spirit of God exherted ministerial powers that consumed the religious adversaries besieging the true Saints. The armies of Chrisenized nations found themselves invigorated to mount a successful resistance to the Islamic resurgence on the brink of breaking through to invade the Christian stronghold of Europe as they had done throughout Africa and Asia. By their ministry, the fires of the Reformation, true believers in Christ & His simple Gospel exerted themselves anew to throw off the threats and retain the reign of the Saints granted them by God at Christ's Return around 70AD. Three hundred years after the crowning of Hildebrandt as Pope (1073AD), John Wycliffe completed his doctorate in theology in 1373AD and began his ministry of reformation. John Wycliffe is lionized as, "The Morning Star of the Reformation."