Then evil will have no further purpose at all... For even this level only sustains evil in order that it should serve as a challenge during the time when this is necessary, and it is necessary only as long as flaws and sins remain. However, when all the souls have completed their mission, evil will have no further place because accusation will have no further relevance since it will no longer be proper to punish. (When there are no sins, there is no accusation and therefore nothing to nourish and sustain evil.)
Moreover, it is man’s choice that gives control in the world either to the holy side or to the Other Side. The intent of the commandments is to put holiness in control and prevent the Other Side from taking control. Since men’s mission will then have been fulfilled and the service whereby they put holiness in total control and removed the power of evil will be complete, there will be no further place for evil. (Evil will be negated because there will be no need for it, since it was created to provide the possibility of repair through free will, and the repair will already be complete through the strengthening of good.)