The good neighbour

Sahl Ibn `Abdullah At- Tustri (may Allah have mercy upon him) reported that, "He had a magian neighbor and from his water closet, there was a hole flowing into the house of Sahl. Sahl used to put a vessel under this flowing hole until all rubbish gathered in it and threw it during the night to conceal himself from the people.

Sahl continued to do that for a long period until the time of his death come. He sent for his magian neighbor and summoned him saying, "Enter this house and look into it. He entered and saw the hole with rubbish flowing from it into the vessel and he said, what is this, which I see? Sahl said this is from a long period; I receive it during the day and threw it during the night. The time of my death has come, and I fear that the manners of other people might not endure you, otherwise I would not tell you.. 

The magian said, O an old man, you treat me in such a way from a long period and I am still indulging in my disbelief? Stretch your hand to me, I testify that there is no god but Allah and that Muhammad is the Messenger of Allah(Sallalhu alahi wasallam). Then the soul of Sahl was taken.

Source: Major sins by Imam Dhahabi