Loyalty and sincere devotion to Allah, brotherhood and solidarity are important attributes of believers. The Qur’an tells that all believers are brothers; they are people sharing the same feelings, who strive for the same end, adhere to the  same book and struggle to reach the same goal. Consequently, solidarity becomes a natural feature of a community made up of believers. Allah commends this attachment of believers in the following verse:

Truly, Allah loves those who fight for His cause in battle array, as if they were a solid cemented structure.(As-Saff, 4)

As related in the verse above, striving in unison for the cause of Allah is at this behest.

And hold fast, all together, by the rope which Allah (stretches out for you), and do not be divided among yourselves; and remember with gratitude Allah’s favour to you; for you were enemies and He joined your hearts in love, so that by His Grace, you became brethren; and you were on the brink of the pit of Fire, and He saved you from it. Thus Allah makes His Signs clear to you, so that you may be guided.(Al-Imran, 103)

Believers are modest people who have fellow feeling and mercy for each other. Therefore, unity and solidarity among them is naturally maintained. But even in a community of this nature, there can be reasons to be cautious; certain erroneous behaviour may cause harm to this solidarity and create an unfriendly atmosphere among believers.

The basic reason for such undesirable behaviours is surely the soul (an-nafs): It is true that a believer is tolerant and warm. Yet, everybody has a wicked side to his soul and in a moment of moral weakness, a person may well be driven by the negative side of the soul; to put it another way, he may be influenced by jealousy, selfishness or ambition.

That is why the Qur’an stresses the impact of these negative aspects of soul as a serious threat to unity among believers. Considering that the soul, which can manifest signs of Satan in the human being, can mislead believers, they should avoid behaving in a manner that will provoke the wicked side of other believers.In the Quran, Allah commands as follows:

Tell My servants that they should be courteous in their speech. Satan would sow dissensions among them: Satan is the avowed enemy of man. (Isra, 53)

The above verse surely gives an important message: Allah commands believers to address each other in the best manner possible (not in a good manner, but in the best manner). Here an important feature of Satan is revealed: Satan aims to create dissension among believers.

The essential method Satan employs to break the unity among believers is to inculcate the feeling of competition in the hearts of believers. In a state of heedlessness, a believer may well succumb to delusions of grandeur and develop an ambition to attain a particular status in society. In such a mood, it is quite possible that he may try to establish supremacy over other believers. Similarly, he may feel envy of his brother for one reason or another. Though the word “envy” may sound like a feeling that may be excused, it actually has a more serious significance: it amounts to an explicit rebellion against Allah. In the Qur’an it is mentioned thus: “Or do they envy mankind for what Allah has given them of His bounty?...” (An-Nisa, 54)As the verse suggests, all favours are bestowed by Allah and being envious of the favours given to others is simply opposing the will of Allah. That is why believers should make a point of avoiding such an attitude. Otherwise, it would not promote conduct which would serve in attaining the will and pleasure of Allah. Besides, as the verse below indicates, it is detrimental to the unity of believers:

And obey Allah and His Messenger; and fall into no disputes, lest you lose heart and your power depart; and be patient and persevering: For Allah is with those who patiently persevere. (Al-Anfal, 46)

It follows that a believer should never let competition or dissension prevail among his brothers. Considering the primitive nature of these feelings, his soul should never be driven by them. Furthermore, he should never arouse envy in others. Being unpretentious and modest eradicates the danger of competition among believers. Another key attribute of a believer stressed in the Qur’an is being self-sacrificing. A believer always gives priority to the needs and wishes of other believers and displays a virtuous spirit. What is more, he takes pleasure in assuming such an attitude. The Qur’an describes this attitude as follows:

But those who before them, had homes (in Medina) and had adopted the Faith,- showed their affection to such as came to them for refuge, and entertained no desire in their hearts for things given to the (latter), but gave them preference over themselves, even though poverty was their own lot. And those saved from the covetousness of their own souls are the ones that achieve prosperity.
(Al-Hashr, 9)

Essentially, envy, rivalry and contentiousness are the three basic factors posing a serious threat to the maintenance of brotherhood and solidarity among the believers. Competitiveness, likely to be aroused by ambition, does harm  the bond of brotherhood. This is indeed detrimental to the soul and leads to moral regression.

It is, therefore, senseless to waste time in hindering the efforts of other believers through competition and envy, while endless opportunities lie ahead of man to earn the good pleasure of Allah. Indeed, competition never prevails in an environment where the common goal is earning the pleasure of Allah. A believer should never forget that a community of believers is like a body in which each organ functions in close cooperation with the others for its general well-being. In this context, believers should see the success of their brothers as if it were their own success. This is quite an important concept. There are numerous verses in the Qur’an stressing the importance of brotherhood. In one verse, a prayer made by believers is recounted:

And those who came after them say: “Our Lord! Forgive us, and our brethren who came before us into the faith, and do not leave in our hearts, any rancour (or sense of injury) against those who have believed. Our Lord! You are indeed full of Kindness, Most Merciful.” (Al-Hashr, 10)

A dispute or controversy among the believers will impair the entire struggle. Such a happening would lessen the unity and power of believers, while strengthening the unbelievers. Indeed, unless believers remain each other’s protectors oppression will prevail. The Qur’an makes the following observation:

Unbelievers are each other’s protectors. Unless you do this, (protect each other), there will be tumult and oppression on the earth, and great mischief. (Al-Anfal, 73)

There are explicit commands on brotherhood and unity among believers:

Do not be like those who are divided amongst themselves and opposed to one another after receiving clear signs: for them there will be a dreadful penalty. (Al-Imran, 105)

They ask you about the spoils of war. Say: “(Such) spoils are at the disposal of Allah and the Messenger: So fear Allah, and end your disputes. Obey Allah and His Messenger, if you are true believers.” (Al-Anfal, 1)

Have nothing to do with those who have divided their religion up into sects. Allah will call them to account: He will in the end tell them the truth of all that they did. (Al-Anaam, 159)

Believers are obliged to be merciful and compassionate towards each other. Modesty is the distinctive attribute of a believer. Arrogance and envy are not characteristic of believers, but unbelievers. Thus believers should avoid being seized by this evil side of their souls and should constantly ask the protection of Allah, repent, and make amends. The end that awaits those who do not curb the evil of the soul is described in the following verse:

O you who believe! if any from among you turn back from the faith, Allah will soon replace them by other people whom He will love as they will love Him, who are humble with the believers, stern towards unbelievers, fighting for Allah’s cause and never afraid of the reproaches of such as find fault. That is the grace of Allah, which He will bestow on whom He pleases. Allah encompasses all, and He knows all things. (Al-Maeda, 54)