Whether Lay or Benezet was influenced by Woolman may be a matter of speculation and debate. The consideration of primary importance is the increasing interest manifested in abolition. The Friends were beginning to realize that slavery was contradictory to the basic principles of their organization. Woolman's real opportunity, therefore, came at the memorable Yearly Meeting of 1758, in Philadelphia--the meeting which Whittier has seen fit to term "one of the most important convocations in the history of the Christian church." All during the early part of the meeting, Woolman remained silent, his "mind frequently covered with inward prayer." But when, towards the close of the meeting, the subject of slavery was brought up, he took such an active part in the discussion that he dominated that part of the meeting. His remarks were simple but impressive.[186] The effect was so immediate that many slaveholders expressed a desire to pass a rule to treat as offenders Friends who in the future bought slaves. But there arose the criticism that the real evil could hardly be cured "until a thorough search was made in the circumstances of such Friends as kept Negroes with respect to the uprighteousness of their motives in keeping them, that impartial justice might be administered throughout." Sober thought prevailed. Many assented to the proposition, and others declared that liberty was the Negro's right. Before the meeting closed, John Woolman, John Scarborough, Daniel Stanton, and John Sykes were appointed a committee "to visit and treat with such Friends as kept slaves."[187] Thus the first important step towards the abolition of slavery was taken. The committee lost no time in setting out on their mission. Such a stupendous undertaking, however, was fraught with obvious difficulties. In the first place, the system of slavery had assumed such large proportions that it required a number of years to visit and treat with any appreciable number of slaveholders. Again, it was by no means easy to persuade slaveholders to give up a possession which meant so much to them in power and wealth. Finally, it was unfortunately true in the eighteenth century, as it is in the twentieth, that an argument of right and justice, based upon Christianity, did not have instantaneous effect upon professing Christians. But Woolman seemed divinely inspired to perform his mission. He travelled extensively and never hesitated to approach Friends on the subject of slavery.[188] At the Yearly Meeting for 1759, he was gratified to learn that a recommendation had been made to Friends "to labor against buying and keeping slaves."[189]