As I remember it, after some powerful "unity-inspiring" words by one of the speakers, a genuinely touched gentleman stood up in the audience and cheered, "Unity! Unity! Long Live Unity!"
Most people seemed to be caught by surprise, but you could hear some people in the audience chanting along – unfortunately, it only lasted for a few seconds and then died out. The program continued without further interruption, and when it was over, everyone went home.
Reflecting on the situation, even years later, I realize more than ever that many Muslims, Sunni and Shia, have a genuine desire for Unity. At least emotionally, there doesn't seem to be a difference in the dreams Muslims have of Unity – we all yearn for that rosy image of starting the Month of Ramadan on the same day, having Eid start on the same day, feeling welcome at every Masjid or Islamic Center, etc.
However, when it comes down to turning our desire for Unity into a practical course of thought and action, without compromising principles of faith, that's where many Shias and Sunnis don't necessarily have a clear picture. How so? Well, let's take the "rosy image" example for starters:
What Unity Is NOT
If we want to start the month of Ramadan on the same day and if we want to start Eid on the same day, which theory do we apply for determining the beginning of a lunar month? Within the Shia school alone, there are multiple verdicts from different scholars on this issue in particular. As a matter of fact, in case you didn't know, there are many verdicts which the scholars differ on in various issues. But do we have to see that as a problem?
No. The way to reconcile these differences is to understand that Islam is a religion in which Truth is the ultimate goal. Academic discourse, as a means to reach Truth, is thus highly promoted.
The first step for each individual is to come to a solid reasoning for his/her own core beliefs (Unity of God, Prophethood, Judgment Day, etc.). Next, because most of us are amateurs when it comes to the study of Islamic jurisprudence, we go back to those experts (the scholars) who have the same core beliefs which we have, in order to benefit from the knowledge they have attained after years of research and study. Using this line of thought, legal differences between scholars can be seen as positive signs of an academic movement toward attaining Truth.
So, does Unity mean that each group should get rid of its beliefs or practices until both sides have nothing left except that which is common between them? Of course not! Think about it: how can you get rid of a true belief? It's something you believe! If it is a belief based on firm grounds, nothing can shake it out of you. As for valid practices, it is because they sprout from well-rooted beliefs that they cannot be eradicated completely either.
In the end, Allah puts it beautifully in the Holy Quran when He says, "There is no compulsion in religion; truly the Right Way has become clearly distinct from error." (2:256)
What Unity IS
All right, then what is Unity?! If we have all these differences, what are we united on?
Well, it's simple. Primarily, as Muslims, we unite on our common beliefs, which make us Muslims in the first place. With that as the baseline, we unite on our understanding of each other's differences, in pursuit of common goals.
When there are touchy subjects that need to be addressed, Unity means that we strive to talk about them academically and in the most respectful way possible – making sure not to offend the brothers and sisters on either side.
Unity is to be well-aware of the attempts to divide Muslims and to proactively seek to solidify the brotherhood between Muslims.
"The Believers are but a single Brotherhood: So make peace and reconciliation between your two (contending) brothers; and fear Allah, that ye may receive Mercy." (49:10)
Imam Khomeini, one of the pioneering leaders in the contemporary movement toward solidifying Islamic Unity, called upon Muslims to unite in the following way: "Muslims should be awake. Muslims should be alert that if a dispute takes place among Sunni and Shia brothers, it is harmful to all of us, and it is harmful to all Muslims. We must pay attention that we are all Muslims, and we all believe in the Qur'an; we all believe in Tawheed, and must work to serve the Qur'an and Tawheed."