Ambarisha Maharaj had brother who was very very sinful. Ambarish tried to preach to him but with no success. So he asked Narada Muni to preach to his brother.
Lord Narada did not wanted but finally he agreed.
When Lord Narada came to see sinful Raja, he was greeted with respect but upon hearing preaching words of Narada Muni Raja started to scream and to throw wine’s bottles on Lord Narada. So Narada Muni had to escape, but from a distance he shouted to Paparaja (sinful king) “When you will be in front of Yamaraj (Lord of death), ask him just one question: What is the result of having Sadhu sanga (association with a pure devotee of God)?
After death Paparaja was certainly taken to Yamaraja’s court. Upon hearing from Citragupta about sins committed by Paparaja, Yamaraja felt compasion and said: You will certainly be thrown to hell for eternity, but I can fulfill your last request now, what do you want?
Hearing such words Paparaja recollected Naradas advice and said: Could you tell me what is the result of having Sadhu sanga?
Lord Yamaraj became amased. He said: I’m sorry, but I here deal with sinners not with Sadhus so I don’t know the answer, but since I’ve promised to fulfill your last desire I’ll take you to Lord Brahma.
And they flew to Lord Brahma presence. Upon hearing such elevated question, Lord Brahma said: I’m sorry I am busy with my duty, and this questions are not within the realm of my creation. You have to go to Lord Siva.
When they arrived to Lord Siva kingdom, after hearing what’s the matter, He said: how can I answer such question? I am busy with such gastly creatures who follow me, I do not deal with this question, it is better to have to ask Lord Narayan himself.
After that they approached Lord Narayan in Vaikuntha (The supreme kingdom).
Hearing such a nice question The Supreme Lord smiled and said, gently: the result is that one is delivered to Vaikuntha by all means. So because you have already brought him here, he will stay and you my dear servants, please go back to do your duties.
Such is a result of Sadhu sanga.
https://www.google.com/search?q=Paparaja