There is a trend amongst some young Muslims, especially on social media to declare fellow Muslims or groups as kafirs, that simply constitutes hate mongering.
Linguistically Kufr in Arabic means to hide and a Kafir is a farmer who buries seeds in the soil for germinating.
In Islamic usage of the term, Kafir means an unbeliever, someone who hides the truth by rejecting belief in God and teaching of Islam.
Some Muslims consider all non-Muslims as Kafirs which is not correct. While others call Muslims who differ from them in details of belief and practice as Kafir, that is simply hate speech.
Takfir or the practice of excommunication, one Muslim declaring another as Kafir in ill-founded accusations is considered haram and is a major sin.
The word Kafir is specifically designated for a person rather than a whole community, a race or followers of a religion.
When Prophet Muhammad (s) received God’s message he was basically the only Muslim when he started to preach what he had learned. During his address to people who were not Muslim he never addressed them as ‘Oh Kafir’ but instead he would say ‘Oh man’ or ‘Oh people’. This tells us that those were not Muslim were simply Human beings (in Arabic – Insaan).
The word Kafir has only been used in the Quran when referring to an unbeliever or an infidel. It was when the Prophet tried to peacefully explain the Divine message to people, over a long period of time and still they denied him, that is when God saw these people who have heard His message from His messenger and but still had contempt for the prophet, He then declared them as Kafir. It was the prerogative of God, Himself only to declare them as Kafir.
Thus kafir are those people who have heard the true message of Islam and even then they have contempt towards the last Prophet and the teachings of Islam. Now it is close to impossible for us to know who God has shown the true message of Islam to or who has heard it and still deny it and therefore wouldn’t it be hard for us to know exactly who is a Kafir and who isn’t. It is something only God can know rather than us human beings.
Finding or naming Kafir is also not something we need to concern ourselves with. We should educate our family about Islam, do dawah work, the usual things that it basically spelled out in the Quran.
Also looking for and naming someone Kafir doesn’t do any good. Once you place a person as Kafir then you allow yourself to hate that person because it’s believed they will end up in hell any way. So why do we do it? We do it because if we point out the ‘bad’ people and we are not like the ‘bad’ people therefore that makes us the ‘good’ people. We show hate for others so we can feel good about ourselves.
Christians, Jews, all non-Muslims are not Kafir by default nor are various different followers of Islam who follow different Schools of Thought.
Kafir is someone bound for hell and the only one who can know this for sure is Allah alone.
Let us leave the judging to Him and concentrate on leading a pious and healthy life without hate.