He united with Mr. Thomas in a letter to four distinguished clergymen of Philadelphia, inviting them to lecture in the Universalist churches in that city on points of doctrinal difference between the parties. The result of the invitation was, finally, the Ely and Thomas discussion. An instance in illustration of Mr. Fuller's aptness in emergencies is given in the "Companion and Register" of 1858. Entering the stage-coach for Utica one day, he found it full of passengers, among whom was a somewhat noted "revivalist" of that time, and his friend, a deacon. Mr. Fuller soon became disgusted with the coarse, brow-beating dogmatism of the revivalist toward the unassuming passengers, and took up the argument against him. Enraged at being foiled in controversy and overmatched in wit, the elder poured out a torrent of abusive language, when Mr. Fuller arrested his vulgar tirade by saying in a dignified and authoritative tone, "Stop, sir! Not another word from your lips! Why, sir, you are making a mere blackguard of yourself. Not another word, sir!" (arresting the reply before it could be commenced). "Not another word, I tell you! Why, you have already disgraced yourself and your profession, and, if allowed to continue, would disgrace the company you are in and the very horses that draw you along!" The mortified man shrunk into his corner, cowed by an imperiousness as much excelling his own in energy and power as it towered above him in dignity and truth. But his deacon was determined not to be put down thus, and spoke up with much spirit, "Sir, this is a free country, and others have a right to speak as well as yourself." "Most certainly, my dear sir," said Mr. Fuller, with one of his beaming looks and in his blandest tones, "most certainly, sir; and I hope you will _exercise_ your right." "Yes, sir; and I _mean_ to exercise it, sir; I'll let you know, sir, that I shall speak as much as I please, sir," said the now enraged deacon. "That's right," replied the very courteous Fuller, "speak on, my dear sir; we wish to hear _you_ speak." "Yes, sir," continued the choking deacon, "and I'll let you know that you can't shut _my_ mouth, sir." "Oh, no, sir,--Heaven forbid that I should attempt it--I want _you_ to speak--so, speak on, sir--we like to hear you." "Yes, sir, and I won't ask your permission, neither! I'll let you know, sir, that _you_ are not my keeper, sir!" said the deacon, now almost bursting with rage. "Certainly not, sir," was the very quiet but smiling reply, "certainly not, sir,--I am a _pastor_, _not_ a keeper of _swine_." A prolonged, hearty laugh from the passengers finally died away, and "there was a great calm." The deacon reclined in sullen silence, and the remainder of the journey was enlivened by pleasant and profitable conversation between Mr. Fuller and the other passengers.