I am staying in non-Muslim country. Here we have Masjid and Jama`a, al-Hamdu Lillah. But something happened, and people in our male-Jama`a stopped trusting each other; they divide into groups. They are all trying to be good Muslims (Insha Allah), but Shaitan made his work. Please, can you write some Du'a on such item, with Ayahs and Ahadith, that people must trust each other. Please, give some advise what to do.

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

In reality, difference among Muslims is one of the worst factors that destroys the Muslim Ummah and makes it likely to disappear. Difference causes enmity, hatred, factionalism and fighting one another. Thus, the Qur'an and Sunnah warn Muslims. Allah Says: {… and be not of AlMushrikûn (the disbelievers in the Oneness of Allah, polytheists, idolaters, etc.). Of those who split up their religion (i.e. who left the true Islâmic Monotheism), and became sects, [i.e. they invented new things in the religion (Bid'ah), and followed their vain desires], each sect rejoicing in that which is with it. } [30: 31-32]. He also Says: {… you should establish religion (i.e. to do what it orders you to do practically), and make no divisions in it (religion) (i.e. various sects in religion). …} [42: 13]
In the same vein, the Prophet (Sallallahu Alaihi wa Sallam) said: "O People! Stick to the Muslim community and avoid separation, three times." [ Ahmad ]
Another Hadith records: "Do not differ in opinion, since difference among those people came before you led them to destruction." [ al-Bukhari ]
Muslims are required to be united, to shun difference and to do their best to be on the straight path, i.e. unity and harmony. Here are some fruitful means that help Muslim achieve such a sublime goal.
1) To hold fast to the Holy Qur'an and Prophetic Sunnah. Teachings of the Qur'an and Sunnah aim at peacemaking between people. Allah Says: {"And verily, this (i.e. Allâh's Commandments mentioned in the above two Verses 151 and 152) is my Straight Path, so follow it, and follow not (other) paths, for they will separate you away from His Path. This He has ordained for you that you may become Al-Muttaqûn (the pious)."} [6: 153].
Also, following the Divine teachings in case of difference constitutes a genuine means to avoid dissension.
Allah Says: {… (And) if you differ in anything amongst yourselves, refer it to Allâh and His Messenger (SAW), if you believe in Allâh and in the Last Day. That is better and more suitable for final determination.} [4: 59].
Here, we state that it is our duty as Muslims, to follow The Qur'an and Sunnah as understood by al-Salaf, the Prophet's (Sallallahu Alaihi wa Sallam) companions and the 2 generations that immediately them. This is example, Insha Allah, will help us to get rid of our own whims as well as help us stay on the straight path, i.e. to avoid subjecting the Qur'anic verses and the Prophetic Hadith to our opinions; otherwise, we'll be misled by our false understanding and our religion will become worthless. Allah Forbid.
2) To have full understanding of the issue in question. Muslims are required to have full understanding of the matter of difference, since in most cases difference results from lack of understanding and ignorance. Furthermore, paying attention of some limited aspect of the issue at the expense of the comprehensive understanding leads to deviation.
Shaikh al-Islam Ibn Taymiyah (may Allah's Mercy be upon him) said: 'Difference among people mostly takes place about small things before achieving full and complete comprehension' .
Furthermore, some people think that just by reading some books they become scholars. So, they try to take the initiative considering themselves as great scholars. Then, they oppose the opinions of scholars, and so, they misguide others.
In this vein, Ibn Umar (RAA) reported that the Prophet (Sallallahu Alaihi wa Sallam) said: "Allah does not grasp knowledge by removing it from (the chests) of slaves; He seizes knowledge by making scholars die. So, when no scholars exist, people will take ignorant persons as their leaders. And when people ask those leaders about something, they give answers without knowledge. Therefore, they went on astray and misled others" [Reported by Imam al-Bukhari ].
3) To know for certain and to examine. Many people judge others depending on narrations of a third party, i.e. without exerting the necessary effort to examine the authenticity of such narrations. Such a state, for sure, causes difference and division among the fold of Muslims, especially if these accounts of events were fabricated.
Then, Prophets were used to making sure of all events and news.
In the Holy Qur'an and by the tongue of Prophet Sulaiman (AS) about the story of hoopoe and its absence: {"We shall see whether you speak the truth or you are (one) of the liars.} [27: 27].
Another verse reads: {… If a rebellious evil person comes to you with a news, verify it, …} [49: 6].
Thus, we state that learning with certainty about something requires: (1) a truthful and just informant, and (2) reliable sources.
4) To be sincere and unselfish while seeking the truth. Self-bias leads to refusal of truth and following whims even though one recognizes that he is wrong and the others are right. No doubt such a position is against the upright path of the righteous. Imam al-Shafie said: 'By Allah! I do not care whether the truth comes by my tongue or the opponent's tongue, i.e. I will accept the truth" .
This means that sincerity and having good intention prevent the appearance of difference, but we need to force ourselves to accept the truth.
5) To think well of others. Allah Says: {O you who believe! Avoid much suspicion, indeed some suspicions are sins. And spy not, …} [49: 12].
This verse clearly states that a Muslim is required to think well of all his Muslim brothers. Also, one should avoid spying, which results from evil thinking. Furthermore, a Muslim is ordered to conceal his Muslim brothers' shortcomings, and to avoid speaking ill of them.
In the Holy Qur'an about the incident of Ifk (falsehood against 'Ayisha (RAA): {Why then, did not the believers, men and women, when you heard it (the slander) think good of their own people and say: "This (charge) is an obvious lie?"} [24: 12].
This verse states that every Muslim is required to take the right position as presented: To think well of oneself and others.
Another verse reads: {When you were propagating it with your tongues, and uttering with your mouths that whereof you had no knowledge, you counted it a little thing, while with Allâh it was very great.} [24: 15]. He also Says: {Allâh forbids you from it and warns you not to repeat the like of it forever, if you are believers.} [24: 17].
The above-verses show us the right way and the best position that a Muslim should take towards such incidents.
Know that having doubts and misgivings about the intentions of the others leads to hatred and differences. Also, interpreting the words of others in a wrong way constitutes injustice to them.
In this concern, 'Umar Ibn al-Khattab (The Emir of the faithful (RAA) said: 'Do not misinterpret any of a Muslim's words as long as there is a possible sign of good' .
Muslims are ordered to understand the other's opinion as shown above. So, difference will be vanished, Insha Allah. We pray Allah to grant all of us His Mercy and Guidance, to bring us together, to unite the Muslims' positions and to make peace between them.
The Prophet (Sallallahu Alaihi wa Sallam) said: "Shall I not inform you the superior act than the fasting, the prayer, the charity, enjoining good and forbidding evil"? They said, 'Surely, O Messenger of Allah!' He said: "Reconciliation between Muslims, spoiling the relations is the shaver. I do not mean that which shaves hair but which shaves one's religion" . Allah knows best.