All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger.
Disputable points of knowledge or practice, either on fundamentals or branches of religion, should be resolved by the Quran and the Sunnah. Allaah The Almighty Says (what means): {O you who have believed, obey Allaah and obey the Messenger and those in authority among you. And if you disagree over anything, refer it to Allaah and the Messenger, if you should believe in Allaah and the Last Day.} [Quran 4:59]
If those who debate such things do not refer back to the Quran and the Sunnah, the truth will not be revealed and there will be disagreement, injustice and aggression, unless Allaah The Almighty has mercy on them.
On the other hand, no person is permitted to give personal opinions on the fundamentals of religion and Tawheed (monotheism)-related issues, and people are not allowed to mix their words with arguments and illusions. Rather, a person’s sources must be the Quran and the Sunnah and consensus of the righteous predecessors. Anyone who speaks of their own accord, believing that it is the true religion of Allaah but not deducing their thinking from the Quran or the Sunnah, is sinful even if he is correct. Moreover, anyone who refers back to the Quran or Sunnah is rewarded, even if he is mistaken. If the person is correct, their reward is multiplied. This is according to Abu ‘Izz, a Hanafi scholar .
Moreover, subtle issues of ‘Aqeedah must not be discussed in the presence of Muslims who are not knowledgeable, who should, rather, be addressed with established general facts approved by the Quran, the Sunnah and consensus, without extraneous details or ambiguous, subtle points. This is the opinion of Shaykh Al-Islam Ibn Taymiyyah .
Allaah Knows best.