Then to be one of those who believe and urge each other to patience and urge each other to mercifulness. Those are the Companions of the Right. (Surat al-Balad: 17-18)
As expressed in the above verse, Allah commands His servants to "urge each other to compassion" in order to attain His mercy, to enter the Garden and to prosper on the Last Day. Believers, who devote their lives to gaining Allah's approval, try to fulfil this order of Allah impeccably. Their sincere faith in Allah underlies this very understanding of mercy. They are aware that nothing occurs unless by the Will of Allah and realise their need to have all His blessings bestowed upon them. Accordingly, believers are humble, which is a consequence of such awareness. These very attributes constitute the basis of their mercy.
One who is not humble in the real sense, cannot show real mercy. That is because he thinks about himself alone, loves himself and gives importance solely to his own wishes and interests. That is why he never considers the needs of others. He deems other people worthless and unimportant. Consequently, he fails to have feelings of compassion and affection.
Another reason why believers are committed to showing compassion is their earnest desire to embody the morality deemed good by Allah. As explained in numerous verses, Allah is "the Most Merciful of the merciful". For that reason, believers strive to experience compassion to the best of their ability.
As Allah revealed in the Qur'an, "If it had not been for the favour of Allah upon you and His mercy, (you would have suffered many difficult situations)." (Surat an-Nur: 20) The above verse shows the extent to which believers are in need of the compassion and mercy of Allah. Since they themselves seek to obtain Allah's Mercy, they try to be as compassionate as possible towards other believers.
As is true of all other issues, the unique guide that sheds light on the kind of mercy they have to show is the Qur'an. Thus, believers only show mercy and compassion in situations deemed to be proper by Allah and towards people specified by Allah.
Mercy as described in the Qur'an emerges as being quite distinct from other kinds of mercy. But the majority of those who are distant from religion possess a rather flawed understanding of the subject. Faced with untoward happenings, they are seized by an ill-defined feeling of mercy and act accordingly. This indeed shows a crude understanding of how they should respond, because they act without knowing who is right or wrong, without making a just and rational assessment and, more importantly, without considering the commands of the Qur'an. Often, they tend to behave in a manner likely to do harm both to themselves and to other people; their attempts to remedy matters are abortive because they take ill-considered decisions. Their understanding of compassion thus presents a structure uninspired by the values of the Qur'an.
In relation to this subject, we need to dwell on another important point. People sometimes harbour an understanding of mercy which may be wrong according to the Qur'an. Since this kind of mercy does harm to people rather than good, it may be considered as "evil compassion". In societies which are indifferent to religion, people allow others to engage in any act without considering its baneful result in the hereafter. For instance, they allow them to behave immorally and turn a blind eye when they engage in an act forbidden by Allah, or even encourage them.
The criteria believers adopt for themselves in this matter is that the mercy shown to others must definitely make a positive impact in terms of others' eternal life in the hereafter. In some cases, the love and mercy they feel for believers may entail their interfering or criticising them on some issues which may be hard on their lower selves (an-nafs). Upon witnessing a wicked deed, they may criticise the perpetrator and make strong pleas to deter him from such a deed. This is indeed true compassion. That is because, at the risk of causing offence to the other party, they put a stop to a conduct at variance with Qur'anic teaching and thus prevent that person from engaging in an act that would incur eternal torment in hell—a point of no return. For that reason, believers encourage others to display the morality with which Allah will be pleased most, and which will prepare them for a life in paradise. In so doing, they display the most elevated form of mercy. One needs to keep in mind that the real cruelty is not to consider the eternal life and to deliberately ignore mistakes that would incur punishment.
In this respect, believers follow the Prophet Muhammad, may Allah bless him and grant him peace, as their role model, who, in the words of the Qur'an, was "truly vast in character". (Surat al-Qalam: 4)
In another verse, Allah reveals the elevated morality of the Prophet, may Allah bless him and grant him peace: "A Messenger has come to you from among yourselves. Your suffering is distressing to him; he is deeply concerned for you; he is gentle and merciful to the believers." (Surat at-Tawba: 128) Thus, in compliance with Allah's command, believers who adopt this morality behave compassionately and mercifully towards believers by considering their rewards in the hereafter.