Assalamu 3laykum,
Shaykh al Islaam Muhammad ibn Abdul Wahab said in his 'Nullifiers of Islam'
3. Whoever does not hold the polytheists to be disbelievers, or
has doubts about their disbelief or considers their ways and beliefs
to be correct, has committed disbelief.
Shaykh Abdullah ibn Jibreen rahimahullah said concerning this:
This nullifier consists of three parts: Firstly, whosoever does not agree that the atheists are disbelievers, when Allah announces in the Qur'an in many verses that they are indeed kuffar (infidels).
Allah says in the Qur'an (of which meaning translates as), "Verily, those who disbelieve [in the religion of Islam, the Qur'an and Prophet Muhammad (PBUH)] from among the people of the Scripture [Jews and Christians] and Al-Mushrikeen, will abide in the Fire of Hell" (98:6). Secondly, whosoever hesitates in the status of the kuffar (infidels) (i.e. he is not sure they are disbelievers or not). Thirdly, whosoever praises the path of the kuffar (infidels) and believes that their religion is correct and that they are on the right path;
this type is even worse than the first two. There are two ints that must be mentioned here:
- When we say the kuffar (infidels) here, we mean those for whom there is no doubt they are disbelievers (i.e. Jews, Christians, Hindus, etc.) and those who claim to be Muslims, but who are believed by the majority of the Muslim scholars to be disbelievers (i.e. Qadianies, An'Nosairiah, Al-Baha'aih, Ad'Drowze, Al-Batiniah, etc.). Sheikh AlIslam Ibn Taymiyyah said, "Whosoever hesitates in the disbelief of those groups after having knowledge of what they say and having knowledge of the religion of Islam, then he is a kaffir (infidel); just as having doubt in the disbelief of the Jews, Christians, and the atheists (Al-Fatawa Vol 2, P368). But for those for whose kufr (infidelity) the scholars dispute, such as the one who abandons As" Salat (the five daily prayers without rejecting its obligation); this does not fall under this nullifier.
- In regards to praising the kuffar (infidels), the Muslim must take great care. If praising them in their faith, this is considered as kufr (infidelity). Whereas praising their behavior (such as their courage or their generosity) is permissible. But one thing the Muslim must avoid, which is considered sinful, is to call a kaffir (infidel) "Mister" as the Messenger (PBUH) said (of which meaning translates as): "When you call the hypocrite 'Mister', you have made your Lord angry" (Reported by An- Nasa'i).
Its also important to remember the ayat of Surah'tul Imraan
81. And (remember) when Allâh took the Covenant of the Prophets, saying: "Take whatever I gave you from the Book and Hikmah (understanding of the Laws of Allâh, etc.), and afterwards there will come to you a Messenger (Muhammad SAW) confirming what is with you; you must, then, believe in him and help him." Allâh said: "Do you agree (to it) and will you take up My Covenant (which I conclude with you)?" They said: "We agree." He said: "Then bear witness; and I am with you among the witnesses (for this)."
82. Then whoever turns away after this, they are the Fâsiqûn (rebellious: those who turn away from Allâh's Obedience).
83. Do they seek other than the religion of Allâh (the true Islâmic Monotheism worshipping none but Allâh Alone), while to Him submitted all creatures in the heavens and the earth, willingly or unwillingly. And to Him shall they all be returned.
84. Say (O Muhammad SAW): "We believe in Allâh and in what has been sent down to us, and what was sent down to Ibrâhim (Abraham), Ismâ'il (Ishmael), Ishâque (Isaac), Ya'qûb (Jacob) and Al-Asbât [the twelve sons of Ya'qûb (Jacob)] and what was given to Mûsa (Moses), 'Iesa (Jesus) and the Prophets from their Lord. We make no distinction between one another among them and to Him (Allâh) we have submitted (in Islâm)."
85. And whoever seeks a religion other than Islâm, it will never be accepted of him, and in the Hereafter he will be one of the losers[].
86. How shall Allâh guide a people who disbelieved after their belief and after they bore witness that the Messenger (Muhammad SAW) is true and after clear proofs had come unto them? And Allâh guides not the people who are Zâlimûn (polytheists and wrong-doers).
87. They are those whose recompense is that on them (rests) the Curse of Allâh, of the angels, and of all mankind.
88. They will abide therein (Hell). Neither will their torment be lightened, nor will it be delayed or postponed (for a while).
And Allah knows best