We do not differ in religious opinions

[This is from my letter to John Adams on August 22, 1813:]

very much suspect that if thinking men would have the courage to think for themselves, and to speak what they think, it would be found they do not differ in religious opinions as much as is supposed. I remember to have heard Dr. Priestley say, that if all England would candidly examine themselves, and confess, they would find that Unitarianism was really the religion of all; and I observe a bill is now depending in parliament for the relief of Anti-Trinitarians. It is too late in the day for men of sincerity to pretend they believe in the Platonic mysticisms that three are one, and one is three; and yet that the one is not three, and the three are not one; to divide mankind by a single letter into ομοουσιανς and ὁμοιουσιανς. But this constitutes the craft, the power and the profit of the priests. Sweep away their gossamer fabrics of factitious religion, and they would catch no more flies. We should all then, like the Quakers, live without an order of priests, moralize for ourselves, follow the oracle of conscience, and say nothing about what no man can understand, nor therefore believe; for I suppose belief to be the assent of the mind to an intelligible proposition.