The Friend was an avid reader who could quote long passages of the Bible and prominent Quaker texts from memory. Using this skill and encouraged by their new mission from God, they traveled and preached throughout Rhode Island, Connecticut, Massachusetts, and Pennsylvania accompanied by their brother Stephen and sisters Deborah, Elizabeth, Marcy, and Patience.
Early on, the Public Universal Friend preached that people needed to repent of their sins and be saved before an imminent Day of Judgment. According to Abner Brownell, the preacher predicted that the fulfillment of some prophecies of Revelation would begin around April 1780, 42 months after the Universal Friend began preaching, and interpreted New England's Dark Day in May 1780 as fulfillment of that prediction. According to a Philadelphia newspaper, later followers Sarah Richards and James Parker believed themselves to be the two witnesses mentioned in Revelation and accordingly wore sackcloth for a time.
Friend would have long outdoor worship meetings or in houses which often attracted large audiences, including some who formed a congregation of "Universal Friends", making The Friend the first American to found a religious community. These followers included roughly equal numbers of women and men who were predominantly under 40. Most were from Quaker backgrounds, though mainstream Quakers discouraged and disciplined members for attending meetings with the Friend. And several members were black. Friend preached hospitality towards everyone no matter their race or gender. Friend believed anyone regardless of gender or race could gain access to God's light and that God spoke directly to individuals who had free will to choose how to act and believe. They also believed in the possibility of universal salvation.
Popular newspapers and pamphlets covered the Friend's sermons in detail by the mid-1780s with several Philadelphia newspapers being particularly critical; they fomented enough opposition that noisy crowds gathered outside each place the preacher stayed or spoke in 1788. Most papers focused more on the preacher's ambiguous gender than on theology. One person who heard the Friend in 1788 said "from common report I expected to hear something out of the way in doctrine, which is not the case, in fact I heard nothing but what is common among preachers" in mainstream Quaker churches.