William's letter opened the jail doors. It is likely, however, that the signature was more influential than the epistle; for his Quaker associates seem not to have come out with him. The fact which probably weighed most with the Lord President was that Penn was the son of his father the admiral, and the protégé of Ormond. His father called him home. It was on the 3d of September that William was arrested; on the 29th of December, being the Lord's day, Mrs. Turner calls upon Mr. and Mrs. Pepys for an evening of cheerful conversation, "and there, among other talk, she tells me that Mr. William Pen, who has lately come over from Ireland, is a Quaker again, or some very melancholy thing; that he cares for no company, nor comes into any." Admiral Penn was sorely disappointed. Neither France nor Ireland had availed to wean his son from his religious eccentricities. Into the pleasant society where his father had hoped to see him shine, he declined to enter. He said "thee" and "thou," and wore his hat. Especially upon these points of manners, the young man and his father held long discussions. The admiral insisted that William should refrain from making himself socially ridiculous; though even here he was willing to make a reasonable compromise. "You may 'thee' and 'thou' whom you please," he said, "except the king, the Duke of York, and myself." But the young convert declined to make any exceptions. Thereupon, for the second time, the admiral thrust his son out of the house. The Quakers received him. He was thenceforth accounted among them as a teacher, a leader: in their phrase, a "public Friend." This was in 1668, when he was twenty-four years old. The work of a Quaker minister, at that time, was made interesting and difficult not only by the social and ecclesiastical prejudices against which he must go, but by certain laws which limited free speech and free action. The young preacher speedily made himself obnoxious to both these kinds of laws. Of the three years which followed, he spent more than a third of the time in prison, being once confined for saying, and twice for doing, what the laws forbade. The religious world was filled with controversy. There were discussions in the meeting-houses; and a constant stream of pamphlets came from the press, part argument and part abuse. Even mild-mannered men called each other names. The Quakers found it necessary to join in this rough give-and-take, and Penn entered at once into this vigorous exercise. He began a long series of like documents with a tract entitled "Truth Exalted." The intent of it was to show that Roman Catholics, Churchmen, and Puritans alike were all shamefully in error, wandering in the blackness of darkness, given over to idle superstition, and being of a character to correspond with their fond beliefs; meanwhile, the Quakers were the only people then resident in Christendom whose creed was absolutely true and their lives consistent with it.