Almost from the beginning of his ministry Fletcher's pen was active in the service of religion. From various causes much, if not the greater part, of his writings was controversial, and to this fact may be assigned, in part at least, their immediate popularity and subsequent neglect. But the spirit of controversy never got the better of the spirit of devotion. Whatever view may be taken of the Calvinist controversy, in which he took a leading part, few will dissent from Southey's judgment: "If ever true Christian charity was manifested in polemical writing, it was by Fletcher of Madeley. Even theological controversy never in the slightest degree irritated his heavenly temper." Some extracts from his earlier writings will show the spirit in which he entered upon this part of his labours.
In reply to the visitation sermon attacking the "doctrines of Methodism," he wrote, in July, 1761, a short "Defence of Experimental Religion," which may be classed amongst the best apologies of the period. He had now acquired an easy, pleasant English style, tending somewhat to the florid and diffuse, but generally stopping short of excess, and often forcible and persuasive in a high degree. He had no difficulty in showing that to represent virtue and morality as the way to salvation is neither agreeable to the Scripture nor to the doctrine of the Church of England. The true nature of justification, and of the faith that justifies, he illustrates from the Articles and Homilies. The necessity of God's grace to turn the will, as against the superficial notion that a man is as free to do good as to do evil, is shown from Article X., from the baptismal office, and the collect for Ash Wednesday.
It was inevitable in the state of religion in England, and considering the chief intellectual influences then in the ascendant, that to preach salvation as a present blessing to be possessed and enjoyed, was to incur the charge of enthusiasm. The high and moderate clergy never felt surer of themselves than when exposing the folly and presumption of "feelings" and "experiences" in religion. Fletcher distinguishes between what is true and what is false on this subject:
"To set up impulses as the standard of our faith or rule of our conduct; to take the thrilling of weak nerves, sinking of the animal spirits, or flights of a heated imagination, for the workings of God's Spirit; to pretend to miraculous gifts, and those fruits of the Spirit which are not offered and promised to believers in all ages, or to boast of the graces which that Spirit produces in the heart of every child of God, when the fruits of the flesh appear in our life--this is downright enthusiasm: I detest it as well as you, sir, and I heartily wish you good luck whenever you shall attack such monstrous delusions.