We have already mentioned its prohibition as well as the evidences for that and what has been reported concerning the punishment for it. We also mentioned its definition, however all of this was brief. We will now add more to its explanation.
Imaam Abu Haamid Al-Ghazaalee (رحمه الله) said:
"For the most part, gossip (nameemah) is attributed to the one who takes the statement of a person (concerning another individual), and relates it back to that individual that is being spoken about. An example of this is when someone says: ‘That person said such and such about you.’ However, gossiping is not limited to just this example, but rather its extent is: Exposing that which one hates to have exposed, whether the one he is relating from or the one he is relating the story to or the third party hates it. And it is the same if this exposing is done by speech or by writing or by gesturing, etc, and regardless whether what is being narrated relates to someone’s sayings or actions, and whether it is a defect or other than that. So the reality of Gossiping is: Spreading what is supposed to be private, and destroying the concealment of what he hates to have exposed.
A person must keep quiet with regard to anything he sees (or hears) from the conditions of people, except for that which if he relates will have a benefit for a Muslim or it will prevent a sin from occurring.”
And he said: “Anyone that has gossip (nameemah) conveyed to him, and it is said to him: 'Such and such person said this about you', then there are six things required from him:
- He must not believe him because the one conveying the news is a gossiper (namaam), and the gossiper is a wicked person (faasiq), so his reports are rejected. 
- He must forbid him from doing that, advise him and declare the detestability of his action.
- He must hate him for the sake of Allaah, for indeed, he is hated in the sight of Allaah and hating for the sake of Allaah is an obligation.
- He must not think evil thoughts about the person he is relating from, based on Allaah’s saying:
‘Avoid much (types of) suspicion.’ [Surah Al-Hujuraat: 12]
- What has been related to you (about someone) should not cause you to spy or investigate further into the matter, because Allaah says:
‘And do not spy on one another.’ [Surah Al-Hujuraat: 12]
- He should not be pleased for himself with what he has forbidden for the gossiper. Thus he should not report the gossip that was conveyed to him by saying: 'Such and such person told me this’, for then he would become a gossiper himself and he would be committing that which he forbade.”
It has been reported that a man went to 'Umar Ibn 'Abd-il-'Azeez (رحمه الله) and said something to him about another person. So 'Umar (رحمه الله) said to him:
“If you wish, we shall investigate your case. If you are lying, then you are from those who fall under the ayah:'If a wicked person comes to you with news, then verify it' [Surah Al-Hujuraat: 6]
And if you are telling the truth, then you fall under the ayah:'Backbiter, going about spreading slander.' [Surah Al-Qalam: 11]
And if you wish, we can overlook the matter.” So the man said: “Please overlook it, O Commander of the Believers! I will never mention it again.”
 Translator’s Note: This is based on Allaah’s saying:
”If a wicked person (i.e. faasiq) comes to you with news, then verify it, lest you harm people without realizing it (i.e. out of ignorance) and afterwards you become regretful for what you’ve done.” [Surah Al-Hujuraat: 6]