Woe Quotes - page 8
Rabbi Elazar, son of Rabbi Shimon, says, ‘Since the world is judged by its majority, and the individual is judged by the majority, if he performs one Mitzva, happy is he, for he has sentenced himself and the whole world to a scale of merit. If he commits one sin, woe unto him, for he has sentenced himself and the whole world to a scale of sin.' (...) Moreover, it is written, "one sinner destroyeth much good.”.
Yehuda Ashlag