-- Gibbon, The Decline and Fall of the Roman Empire, chapter 54 (quoted here).
...the loss of one mystery was amply compensated by the stupendous
doctrines of original sin, redemption, faith, grace, and predestination, which
have been strained from the epistles of St Paul. These subtle questions had most
assuredly been prepared by the fathers and schoolmen; but the final improvement
and popular use may be attributed to the first reformers, who enforced them as
the absolute and essential terms of salvation. Hitherto the weight of
supernatural belief inclines against the Protestants; and many a sober Christian
would rather admit that a wafer is God, than that God is a cruel and capricious
... As one might expect, Gibbon has a good word for Erasmus, "the father of rational theology," whose followers "diffused a spirit of freedom and moderation." (For a practicing Lutheran, I have always had a soft spot for Erasmus.) Gibbon indeed thinks Erasmus triumphant, in practice if not in theory:
The volumes of controversy are overspread with cobwebs; the doctrine of a Protestant church is far removed from the knowledge or belief of its private members; and the forms of orthodoxy, the articles of faith, are subscribed with a sigh or a smile by the modern clergy.