The first question is, why have some Muslims been called disbelievers? Allah Almighty says that a person can be a Muslim while not being a believer.
The Arabs of the desert say, ‘We believe.’ Say, “You have not believed yet; but rather say, ‘We have accepted Islam,’ for the true belief has not yet entered into your hearts.”(Surah al-Hujurat, 49:15)
The Messenger of Allah(Sunan an-Nasa’i, vol. 6, Book 47, Hadith 4,996)
sasdistributed (some spoils of war) and gave to some people but withheld from others. I said: “O Messenger of Allah, you gave to so-and-so and so-and-so, and you withheld from so-and-so, who is a believer.” He said: “Do not say ‘a believer,’ say ‘a Muslim.’” Ibn Shihab (one of the narrators) said: “The Arabs of the desert say: ‘We believe.’”
This concept was also explained by the Holy Prophet sas elsewhere:
The one who commits an adultery/fornication is not a believer at the time of committing adultery/fornication and a thief is not a believer at the time of committing theft and a drinker of alcoholic drink is not a believer at the time of drinking.(Sahih al-Bukhari, Book 86, Hadith 40; Sahih Muslim, Book 1, Hadith 114)
Hadrat Khalifatul-Masih IV rta explained this further:
The opposite of a believer is a disbeliever, and the opposite of a Muslim is a non-Muslim and in these two things God has placed a difference—for God says [to the Holy Prophet(Extreme Lies and Verdicts of Disbelief Against the Founder of the Ahmadiyya Muslim Jama‘at, p. 5)
sas: Tell them that God, Who is the Knower of the Unseen, has given me the knowledge that belief has not yet entered in your hearts. Therefore, do not claim to be mumin[believer], but we do not take away your right to call yourselves Muslims.
From the very beginning, Muslims who were weak of faith were referred to as disbelievers, and this did not infringe in any way on their right to call themselves Muslims. The same way in which the Holy Quran and the Holy Prophet
We believe that the term kafir applies to a person after he has passed beyond a prescribed limit. When a person takes Islam as his religion and accepts the Quranic injunctions and teachings as his guide of action, he is entitled to be called a Muslim. But if he denies a basic principle of the faith of Islam, then although he may be called a Muslim, yet in(Review of Religions, July 1935, April 26, 1935, p.14)
realityhe is not so. We do not thereforetake kafir to mean that such a person denies the Holy Prophet Muhammad sas. Who can say to a person who says that he believes in the Holy Prophet that in realityhe has no such faith? Nor do we take this term to mean the denial of the existence of God. One who says that he has belief in God, who can dare say that he has none? According to our definition of kufr, the denial of a fundamental doctrine of Islam renders a person kafir. On the other hand, only belief in all the essentials of Islam can make a person a true Muslim in the real sense of the word.
The second question is, why have some Muslims been called non-Muslims? The answer is that there are two categories of non-Muslims. First are those who outwardly are non-Muslims; this can even refer to innocent disbelievers.
Those who do not accept a prophet, even if it is only because they have never heard his name, they are referred to as disbelievers, although in the sight of God they are not deserving of punishment because their disbelief was not because of any fault of theirs.(A’inae-Sadaqat, p. 31)
Second are those who outwardly are Muslims but inwardly are not true Muslims. Hadrat Musleh Mau‘ud ra explained that there are different stages of the word Muslim, which has been explained in the renowned dictionary:
Mufradat-e-Raghib on page 240, where Islam has been shown to be of two kinds: one lower than the stage of Iman; the other above the stage of Iman. In dun-al-iman, in the stage of lower than common Iman, are included people whose Islam remains at a level lower than a proper Iman, and in the stage of higher than the common Iman are Muslims who stand at a level of distinction in their faith, higher than the common level.(Truth Prevails, p. 154)
By definition, there are two stages of Muslims, dun-al-iman [lower than faith] and fauq-al-iman [higher than faith]. Those who are only Muslims in dun-al-iman are not Muslims in fauq-al-iman. These Muslims are referred to as non-Muslims in this context, but they are never deprived of their right to call themselves Muslims. For example, the Holy Prophet sas said:
Where a man sallies forth to give support to an unjust person, knowing that he is unjust, the supporter thereby throws himself outside the bounds of Islam.(Mishkat, Kitabul-Adab, Bab-uz- Zulm, vol. 2, p. 555)
Also, the Promised Messiah as said:
Now let it be quite clear that these days the doctrine of some believers in the unity of God, that in species of birds, some are the creation of the Lord God, and some of Hadrat ‘Isa, is entirely misleading and idolatrous. The person who holds this view, without any doubt, is outside the pale of Islam.(Ruhani Khaza’in, vol. 3, p. 252)
These stages of Islam become even more refined based on context. For example, one stage of submission, or Islam, is described as far above the category of faith when the Holy Quran narrates about Hadrat Ibrahim as:
When his Lord said to him, ‘Submit,’ he said, ‘I have submitted to the Lord of the worlds.’(Surah al-Baqarah, 2:132)
Here, a great prophet of God, who is on the highest stages of faith, is commanded to attain the stage of Islam. However, in a different context, the Holy Quran uses this same word to refer to a stage that is far lower than faith when it says:
You have not believed yet; but rather say, ‘We have accepted Islam.’(Surah al-Hujurat, 49:15)
A person can be a non-Muslim by one stage and a Muslim by another stage. From the very beginning, the term Muslim has been used to refer at times to those who were the weakest of believers and at times those who were the strongest of believers. This never infringed in any way on their right to call themselves Muslims. The same way in which the Holy Quran and the Holy Prophet
When outward Muslims were referred to as disbelievers and non-Muslims by the Holy Prophet
There is a telling difference between the position of non-Ahmadi Muslims and Ahmadi Muslims on takfir. When an Ahmadi Muslim is asked if non-Ahmadi Muslims should call themselves Muslims, we must say that not only do they have every right to call themselves Muslims, we insist that they do so. This is in perfect line with the precedent of the Holy Quran and Holy Prophet