Firstly:
The human is a weak creature; he is faced with both good inclinations and evil inclinations, and he may sometimes lose control and find himself driven towards the path of immorality and deviance, and driven by evil inclinations to the path of wrongdoing and transgression, as the Shaytan makes doing bad things fair seeming to him.
But man's inclination towards the good stirs his conscience, makes him feel remorse and urges him to return to the path of truth and respond to the call of reason.
People vary in their potentials, willpower, and how pure at heart they are. Some of them train themselves to walk in the path of virtues and noble characteristics, and urge themselves to adhere to sublime principles and ethics, and to resist desires and evil inclinations; they force themselves to adhere to the straight path and to be fair and just. Such a person will be able to confront evil and put up with all difficulties for the sake of defeating evil, and he will never lose hope that goodness will prevail and evil will be defeated and vanish. Others give in to their whims and desires, and are unable to force themselves to adopt virtuous characteristics and act in accordance with them. They neglect many of the commands of Allah and His Messenger; they feel too weak to resist evil and lose hope of good ever prevailing.
The key to success in this issue is to strive against one’s whims and desires, and the nafs (self) that is inclined to evil, in order to attain guidance from Allah. Allah, may He be Exalted, says: {As for those who strive hard in Our cause, We will surely guide them to Our paths} [Al-`Ankabut 29:69].
Imam Ahmad (23958), Ibn Hibban (4862) and others narrated that Fadalah ibn `Ubayd said: The Messenger of Allah (blessings and peace of Allah be upon him) said during the Farewell Pilgrimage: “Shall I not tell you about who is the believer? The one from whom people are safe with regard to their wealth and their lives. The Muslim is the one from whose words and actions the people are safe, the mujahid is the one who strives against his nafs in obedience to Allah, and the muhajir is the one who avoids (hajara) sins.”
Classed as authentic (sahih) by at-Tirmidhi and al-Hakim, and by al-Albani in As-Sahihah, 549.
Ibn al-Qayyim (may Allah have mercy on him) said in Zad al-Ma`ad (3/6):
Striving (jihad) against one’s nafs takes precedence over striving against external enemies, and it is the foundation thereof, for the one who does not strive against his nafs and evil inclinations first, forcing himself to do what is enjoined and to refrain from what is prohibited, striving against his nafs for the sake of Allah, will not be able to strive in jihad against the external enemy. How can he strive in jihad against his enemy and settle scores with him, when the enemy (his nafs) that is inside him has control over him and is suppressing him, and he is not striving against it or fighting it for the sake of Allah? Rather he will not be able to engage the external enemy until he strives against his nafs to force it to go out and meet the enemy. End quote.
To sum up: if the Muslim strives against his nafs and forces himself to keep away from sin and do acts of worship and righteous deeds in compliance with the commands and prohibitions of Allah, may He be Exalted, he will be rewarded for that – in sha Allah – commensurate with the effort he put into striving against his nafs for the sake of Allah.
Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him) was asked:
Which is more appropriate to pay attention to and deal with: is it what Allah dislikes you to have in your heart of envy, grudges, rancour, arrogance, showing off, love of reputation, admiring one’s own deeds, hard-heartedness and so on, which are diseases of the heart and indicative of the evil and dirt in it? Or is it focusing on doing physical, visible acts of worship, such as prayer, fasting and other acts of worship, supererogatory actions and fulfilment of vows, despite having those problems in one’s heart? Please advise us.
He (may Allah have mercy on him) replied:
Praise be to Allah. Some of that is obligatory for the individual, and what is more obligatory and takes precedence over that is what Allah, may He be Exalted, said in the hadith qudsi that was narrated from the Messenger of Allah (blessings and peace of Allah be upon him): “My slave does not draw closer to Me by anything more beloved to Me than that which I have made obligatory upon him.” Then He said: “My slave continues to draw closer to Me by doing nafl (supererogatory) deeds until I love him.”
Visible actions cannot be righteous and accepted unless the heart is sound, for the heart is the king and the other faculties are his followers, so if the king is evil, then his followers will be evil. Hence the Prophet (blessings and peace of Allah be upon him) said: “Verily, in the body there is a piece of flesh which, if it is sound, the entire body will be sound, but if it is corrupt, the entire body will be corrupt. Verily it is the heart.”
Similarly, deeds of the heart (emotions and feelings) inevitably have an impact on physical actions, and if there is an action that is more obligatory, then it should be given precedence, whether it is called hidden or apparent. If something that is called hidden is more obligatory, such as giving up envy and arrogance, then it is more obligatory than observing supererogatory fasts.
Some physical, visible actions may be of greater virtue, such as offering voluntary prayers at night (qiyam al-layl); that is better than merely giving up some negative thoughts that cross the mind, such as positive jealousy (ghibtah) and the like.
Both hidden and visible actions support one another. Prayer deters one from indecency and wickedness, and it generates humility, among other great impacts that it has; therefore it is the best of deeds. And something similar may be said about charity. And Allah knows best.
End quote from Majmu` al-Fatawa, 11/381-382.
For more information, please see the answer to question no. 21673.
Secondly:
It says in Al-Mawsu`at al-Fiqhiyyah, 18/5 ff:
Resentment means holding a grudge, harbouring hatred and enmity in the heart, and looking for an opportunity to hurt someone or thinking ill of people because of enmity or a desire for revenge. That is because if a person has to suppress his anger because he is unable to express it immediately, it settles in the heart and develops into resentment.
The ruling on grudges and resentment varies according to the reason for it. If it stems from envy and rancour for no good reason, then it is blameworthy according to Islamic teachings, because it stirs up enmity and hatred, and causes harm to people for no wrongdoing on their part.
It is condemned in the religious texts, including the verse in which Allah, may He be Exalted, condemns the hypocrites who were upset because the believers had attained such harmony and unity among themselves that their enemies were unable to hurt them: {When they meet you they say, “We believe.” But when alone, they bite their fingertips in rage} [Al `Imran 3:119].
What takes away resentment and grudges is giving gifts and shaking hands, as the Prophet (blessings and peace of Allah be upon him) said: “Exchange gifts, for gifts take away grudges of the heart.” And according to another report: “Exchange gifts and you will love one another.”
But if the grudges and resentment are towards an oppressor whose oppression cannot be warded off, or from whom it is not possible to take one's dues, or a disbeliever who is harming the Muslims and they cannot ward off his harm, then it is not blameworthy according to Islamic teachings. Then after that, if a Muslim gains power over the one who oppressed him, he may pardon him, and that is kindness and generosity, or he may take his dues from him, and there is no blame on him for that, because Allah, may He be Exalted, says:
{But whoever settles the score after having been wronged, there is no reason to reproach them. But there is reason to reproach [and punish] those who wrong people} [Ash-Shura 42:41-42].
End quote.
