The fire and intensity of the early Quaker vision, in this writer’s opinion, derived from their passionate insistence that the command “Be perfect” meant exactly what it says and that no excuses, qualifications or hemming and hawing were acceptable. Other Christians would and still say that to live according to the demands of the Sermon on the Mount is unrealistic and represents a standard that is applicable only to life in the hereafter or after the Second Coming. Then we will be pacifists. Now we must wage war against our neighbors because they are willing to wage war against us and we must at least be able to defend ourselves. Perfect honesty will be possible in heaven, but now a little deception once in a while is essential. Fox called such arguments for compromise with the world’s standards “pleading for sin” and he thought that those who so pleaded were mere “professors” i.e. ones who merely profess to be Christian but do not live as followers of Christ.
Source: A Place to Stand: Be Perfect Now