http://revach.net/article.php?id=4360

Section: Stories   Category: Gadlus
The Kotzker Rebbe Exposes The "Yetzer Hara's Tzaddik"
The Chozeh of Lublin had a falling out with the Yehudi HaKadosh of Peshischa after one of the senior and most Choshuveh Chassidim from the Chozeh's court told false reports about the Yehudi HaKadosh.

The Kotzker Rebbe, who followed the Yehudi HaKadosh, said that we see from here the evil and conniving ways of the Yetzer Hara.  This senior Chasid was a no tzaddik.  However the Yetzer Hara did not interfere with his Avodas Hashem and even helped him his whole life in order that one day late in his life when he tells Motzi Shem Ra to the Chozeh, he would have good standing.  Then his malicious lies would be accepted by the Chozeh and cause machlokes.  Watch out, the Satan is smart and patient investor.  And Lashon Hara is a worthwhile investment for him.