Quakerism in terms of its theology, began in 1647 when the twenty-three-year-old Fox had reached a low point in his search for true spirituality.
"Now after I had received that opening from the Lord that to be bred at Oxford or Cambridge was not sufficient to fit a man to be a minister of Christ, I regarded the priests less and looked more after the dissenting people. As I had forsaken all the priests so I left the separate preachers also, and those called the most experienced people: for I saw there was none among them all that could speak to my condition."
Still not satisfied in his spiritual quest, he began spending time with the dissenters and moving around the army camps which were where the most radical religious ideas of the day were circulating. Yet, no one was able to respond adequately to his soul's search. Only when thrown into the inward as opposed to the outward, did he feel met in his struggle.
"And when all my hopes in them and in all men were gone, so I had nothing outwardly to help me, then I heard a voice which said, "There is one, even Christ Jesus that can speak to thy condition" My heart did leap for joy.
This was not simply an adequate answer. It was a radical and revolutionary experience which cut across much church teaching of the time. It became foundational for the emerging Quaker movement and remained central even in its later, multiple and diverse forms. Fox discovered that one, even Christ, could speak to him directly.
From: An Introduction to Quakerism p. 19 Pink Dandelion