I’ve never used the term myself, but I’ve seen it used quite often as a slur against others with whom the user of such a term disagreed with. The article below has an interesting take on such a word, and I’d recommend those who claim to follow the Salaf, who claim to follow the Qur’aan and Sunnah, have a read and then discuss further their knowledge on this topic:
by Shaykh Hamid al-Hamid
“You heretic! I swear by God, I will do you in!”
Who shouted these words? To whom were these words uttered? It was the Abbasid Caliph al-Mahdî who said these words. He said them to none other then the illustrious and celebrated judge Shurayk b. `Abd Allah al-Nakha`î.This word “heretic” – zindîq – How much grief and misery has been caused by it over the centuries? How much has it been abused and used for various ignoble ends?
“Heresy” – zandaqah – laws have been enacted about it. Books have been written on it. People have sought to describe it. Theologians have tried to define it. Nevertheless, Islam never came with it.
The word for it – zandaqah – was alien to the Arabic language during the early years of Islam. It is a Persian word. The concept that it communicates derives from Zoroastrian thought.
The ancient Persians had used the term zandaqah to describe those who interpreted their scriptures – the Avesta – contrary to their literal meanings. More particularly, the term was used to describe Mani and his followers the Manichaeans.
This term and the notion it refers to were initially alien to Islamic thought. Allah never makes reference to it in the Qur’ân. The Prophet (peace be upon him) never brought it in the Sunnah. It is not part of Islamic teachings.
The sacred texts speak of three categories of people. There are the Muslims, the unbelievers, and finally the hypocrites. As for the hypocrites, they are to be treated no differently than the Muslims in this world. Their fate rests with their Lord.
With respect to Islam, there are only believers and unbelievers. Allah says, “It is He who created you. Among you are those who disbelieve and those who believe.”
The term “heretic” remained unknown to Islamic discourse during the era of the Rightly Guided Caliphs. It was also unheard of during the Ummayad Era. Only when the Abbasid dynasty ascended to power in the Muslim world – a dynasty that was essentially Persian in outlook and culture – did the term gain currency in Muslim society. This is not surprising, since the Abbasid court and political machinery were dominated by Persian officials and intellectuals.
The popularity of this term during Abbasid times and the role that it played in Abbasid politics – in their staking their claims to power and in negating those of their opponents – indicates to us that the term might in fact be more political in nature than religious. This makes it a questionable and wasteful practice to try and derive religious teachings and edicts on the basis of this term – that is if we are trying to represent Islamic teachings authentically and accurately.
It is always best to keep our religious discourse upon the terms of Islam and avoid extraneous terms that, even when they turn out to be harmless, fail to make any useful contribution.
When new terminology is introduced into religious discourse, it is rarely adopted in a vacuum. Often there are political motives behind it – and those motives are often loaded with a variety of vested interests. In the case of the word zandaqah and the notion of heresy that it introduced, the motives were political. Sometimes they are sectarian or factional. They usually stem from one sort of conflict or another.
Therefore, it is often useful to investigate the historical origins of the terminology that people use. This can often help us get to the root of some deep-seated and long-lasting problems. When the underlying cause of the conflict is revealed, the problems can be resolved and the terminology of dissention and factionalism – that causes so much grief and misery for society – can be dispensed with.
Why should we let ourselves be divided by terminology we blindly inherited, saying, “This is what we found our forefathers of old upon.” The guidance that Allah has given us is far greater than the ideological notions of our forefathers. Will we not take heed?