For the Protestant Reformers, and for many Protestants today, justification by faith alone (sola fide) isn’t just the biggest issue separating Protestants from Catholics. It is “the central, chief article by which the Christian doctrine and the Christian Church stands and falls,” and without this teaching, Luther claimed that “the church of God cannot subsist one hour.” But is any of that true? Or did the Church subsist for 1500 years before the Reformers invented sola fide? Here’s what the finest Protestant scholars have to say about early Christianity̷…