Backbiting, attaching labels, insulting one another by nicknames, spreading rumors and suspicions about others are major sins in Islam. These are despicable acts in the sight of Allah. The following verses are very clear on this issue:
“O you who believe! Let not a group scoff at another group, it may be that the latter are better than the former; nor let (some) women scoff at other women, it may be that latter are better than the former, nor defame one another, nor insult one another by nicknames. How bad is it, to insult one’s brother after having Faith. And whosoever does not repent (tauba), then such are indeed the wrongdoers (Zaalimeen)" (49:11)
“O you who believe! Avoid much suspicions, indeed some suspicions are sins. And spy not, neither backbite one another. Would one of you like to eat the flesh of his dead brother? You would hate it (so hate backbiting). And fear Allah. Verily, Allah is the one Who accepts repentance (tauba), Most Merciful.” (49:12)
The Prophet (PBUH) in an authentic hadith said:
Do you know what backbiting is? They (the Companions) said: Allah and his messenger know best. Thereupon he (the Prophet) said: “Backbiting implies your talking about your brother in a manner which he does not like.” It was said to him: What is your opinion about this that if I actually find (that failing) in my brother which I made a mention of? He (the Prophet) said: “If (that failing) is actually found (in him), you in fact backbited him and if that is not in him, it is slander (buhtaan).” (Sahih Al-Muslim)
Also, we are asked by Allah to seek refuge from the evil of whisperers (114:5-6).
The Quran also mentions that the technique of furtive whispering to others is used by the devil.
“Then began Satan to whisper suggestions to them…” (7:20)
This is a dishonorable way to function. Instead of coming into the open and providing clear evidence, such people secretly whisper and incite others to follow rumors and suspicions. But, it is equally despicable and dishonorable to fall prey to such rumors and suspicions, which happens when we do not verify facts.
Some Muslims, even Islamic scholars, use this technique to discredit those who differ from them. The history of Muslims provides clear evidence of how this technique was used to crush a difference of opinion. The blood of a large number of Muslims (who differed from the established hierarchy), was spilled by Muslim kings. In our own time, just look around the Muslim world today – Afghanistan, Algeria, Egypt, Iraq, Libya, Syria, and Turkey just to name a few — where (political and religious) battle lines are drawn between different groups of Muslims. Indeed, we, each one of us, need only to look at our own actions! Creating groups or sects in Islam is Shirk according to the Quran (30:31-32) and our Prophet (PBUH) has nothing to do with them (6:159).
“And do not be like the Mushrikun. Those who split up their religion, and become sects, - each sect rejoicing in that which is with itself.” (30:31-32)
“As for those who divide their religion and break up into sects, you (Muhammad) have no part in them in the least.” (6:159)
According to Ummul Momineen ‘Aisha (R), our Prophet (PBUH) was a walking Quran. So, how could our Prophet (PBUH) say anything or do anything against the Quran? How can any Muslim believe that our Prophet (PBUH) was just a postman, when, in fact, he received the revelation from Allah, transmitted it faithfully, and lived his life according to it and successfully implemented it as the constitution to govern the life of the Muslim community?
Let us not be self-righteous, passing judgement against other Muslims who do not follow our own line of thought. Let us try to be tolerant, openhearted, and generous like our Prophet (PBUH) was. This is a very good Sunnah for us to practice.