Islam calls Muslims to unity. If some Muslims fail to comply and achieve unity, then Islam itself is not to be blamed, since we have to judge Islam according to its sources (the Qu’ran and the Sunnah) but never through the practices of some Muslims.
Sheikh Ahmad Kutty, a senior lecturer and an Islamic scholar at the Islamic Institute of Toronto, Ontario, Canada, states: The fact that Muslims are divided cannot be adduced as evidence to discredit the truth of Islam. The reason why Muslims are divided into sects, like anyone else, is due to human failings and weaknesses. Allah says, (Humankind has been created weak!) (An-Nisaa’ 4: 28)

Truth is there for everyone to perceive and experience, but many people refuse to recognize the truth or fail to see it because of their sins, which blur their spiritual vision.
Therefore, the truth of Islam must not be judged on human failings or misconceptions; truth must be judged on its own terms. Islamic principles are true in and of themselves and can be proven true regardless of whether anyone follows it or not. There is nothing in Islam that contradicts sound reason or common sense. Take for instance the following case: Doesn’t everyone know that alcohol, adultery, murder, etc., are awful and degrading sins; yet does this knowledge make them abstain from indulging in them? Does their behavior lessen the sinfulness of those actions? How many people know that smoking is harmful, yet does this knowledge make them abstain from it? Can anyone refer to smoking and say that it is not harmful?
So, I advise that we judge Islam not by the actions of some Muslims but by its own merit. We should examine the teachings of Islam, in light of sound reason and common sense as many have done, and then we will certainly vouch for the intrinsic rationality and soundness of Islamic teachings. We will find them absolutely conducive to attaining human peace, tranquility and happiness. How can they be otherwise, when they are instituted for us by our Creator Who alone knows what is ultimately good for us and what is harmful for us.