January 25, 98: Upon the sudden death of Emperor Nerva, Trajan takes the throne. In 110, he asked Pliny the Younger to investigate a new superstition, "Christianity." Pliny's report of a relatively harmless though widespread cult led to moderate persecution—and the first recognition that Christians were distinct from Jews (see issue 27: Persecution in the Early Church).
January 25, 1627: Noted physicist and chemist Robert Boyle is born in Ireland. After a lifetime of writing about science, religion, and harmony between the two, he underwrote an annual eight-lecture series defending Christianity against unbelievers (see issue 76: Christian Face of the Scientific Revolution).
January 25, 1841: Anglican clergyman John Henry Newman publishes Tract 90 (in a series begun in 1833), an argument for a catholic interpretation of the Thirty-nine Articles. It was the pinnacle of the Oxford Movement, but the last straw for the bishop of Oxford and others. Newman was forced to resign his parish, and he converted to Roman Catholicism four years later.
January 25, 1907: Social reformer and author Julia Ward Howe, composer of the "Battle Hymn of the Republic," becomes the first woman elected to the National Institute of Arts & Letters (see issue 33: Christianity and the Civil War).
January 25, 1959: Ninety days after his election to the papacy, Pope John XXIII announces his intention to hold an ecumenical church council. The Second Vatican Council opened October 11, 1962, and was the Catholic church's most searching self-examination ever (see issue 28: The 100 Most Important Events in Church History).
July 18, 64: The Great Fire of Rome begins, and to direct suspicion away from himself, young Emperor Nero blames the city's Christians. A persecution followed in which Christians were (among other punishments) burned alive (see issue 27: Persecution in the Early Church).
July 18, 1504: Henry Bullinger, Ulrich Zwingli's successor as chief pastor of Zurich and a close associate of Cranmer, Melanchthon, Calvin, and Beza, is born in Switzerland (see issue 4: Ulrich Zwingli).