Difference of Opinion
Faqihul Ummah Mufti Mahmood Hasan Gongohi states, from the aforementioned it becomes clear, in the light of the Quraan and Hadith, how necessary and important it is for us to maintain unity, and how disastrous is disunity. But if we look into history we find that the Sahaba had various differences of opinion. The Imams have differences in various Masa`il. Great Ulema and Scholars of Deen have different rulings and decisions in every era. So the question arises, why is this so? Does it not contradict the concept of unity?
As an answer, it seems appropriate to present notes of Mufti Muhammad Shafi رحمة الله عليه the Grand Mufti of Pakistan. He writes, “First and foremost I would like to make this point clear, that in those Masa`il in which there is room for for logical deductions by learned Scholars of Islam, differences of opinion is not harmful. There is no need to get rid of these differences, nor can they be wiped out. Differences of opinion is neither contrary to the unity of Islam nor is it harmful to anyone. It is but a natural matter, from which no group can remain aloof.
For an entire group of people to be united upon every affair is only possible in two cases: Firstly, when no individual in the group has the potential and the initiative to ponder over a problem and thereby come to a solution. In this case whatever any person suggests, will be just perfect for the rest of the group. Secondly, when there are traitors and hypocrites within a group. In this case they will not expose the flaw in the suggestion showing their agreement, although such an opinion may be harmful in their knowledge.
Wherever there are both the qualities of insight and trust, to avoid a difference of opinion is impossible. Therefore it, in itself is not abominable. If one were to take a survey of affairs and dealings, he will find that instead of proving to be harmful, differences of opinion produce grand results. Mashwera (mutual consultation) has been emphasized in the Shariat for the very same reason i.e. the problem may be viewed from various angles to facilitate a decision of insight. If difference of opinion is reprehensible then it will defeat the purpose of Mashewera (mutual consultation).
(Extracted from Boundaries of differences from the discourses of Faqihul Ummat Mufti Mahmoodul Hasan Gongohi pg.47 & 48)
 
{Unity is not in having the same opinion that is Unanimous rather unity is to live with each other despite differences of opinion.}