Backbiting

من كان يؤمن بالله واليوم الآخر فليقل خيرا أو ليصمت

“Barang siapa yang beriman kepada Allah dan hari akhir maka hendaknya dia berkata yang baik atau diam.” (HR. Bukhari dan Muslim)

In order to avoid backbiting, Muslim are advised to just shut up! 

Backbiting/bitching/ghibah/mengumpat is haram.

يَا أَيُّهَا الَّذِينَ آمَنُوا اجْتَنِبُوا كَثِيرًا مِنَ الظَّنِّ إِنَّ بَعْضَ الظَّنِّ إِثْمٌ وَلا تَجَسَّسُوا وَلا يَغْتَبْ بَعْضُكُمْ بَعْضًا أَيُحِبُّ أَحَدُكُمْ أَنْ يَأْكُلَ لَحْمَ أَخِيهِ مَيْتًا فَكَرِهْتُمُوهُ وَاتَّقُوا اللَّهَ إِنَّ اللَّهَ تَوَّابٌ رَحِيمٌ

“Hai orang-orang yang beriman, jauhilah kebanyakan prasangka (kecurigaan), karena sebagian dari prasangka itu dosa. dan janganlah mencari-cari keburukan orang dan janganlah sebagian kalian menggunjingkan (ghibah) sebagian yang lain. Adakah seorang di antara kamu yang suka memakan daging saudaranya yang sudah mati? Maka tentulah kamu merasa jijik kepadanya. dan bertakwalah kepada Allah. Sesungguhnya Allah Maha Penerima taubat lagi Maha Penyayang.” (QS. Al-Hujuuraat: 12)

"O you who believe! Avoid much suspicion, for some suspicions are a sin. Do not spy on one another, nor backbite one another. Would one of you love to eat the flesh of his dead brother? Nay, you would abhor it, [so similarly, avoid backbiting]. And fear Allah. Indeed, Allah is Most Forgiving, Most Merciful." Qur'an, [49:12]

Muslims should also turn away from a ghibah conversation. Nowadays ghibah has become a big and popular. In tv and magazine you'll find the celebrities gossip slot. Its ghibbah obviously. Gossipping is Ghibah. Listening or reading on gossip is haram as ghibbah. Let us fear ghibbah- and the punishment for ghibbah.

Abu Dawud has reported that the Prophet (peace be upon him) said, ‘When I was taken up to heaven (i.e. during the Mi`raj) I passed by people who had nails of copper with which they were scratching their faces and their breasts. I said, ‘Who are these [people], O Gabriel?’ He replied: ‘They are those who consumed the flesh of people [i.e. backbite them] and aspersed their honor.’

And Allah, the Exalted knows best.

Do read more on exceptional of ghibah here.