The Most Beloved Prophet (Salla Allahu ta'ala alayhi wa Sallam), said to his companions returning from a battle:"You have returned from a smaller battle to a greater battle." He was then asked by the companions, "What can be a greater battle than that we have just fought?" He (Salla Allahu ta'ala alayhi wa Sallam), answered,"The battle against one's nafs".
"The ego (nafs) is the lowest dimension of man's inward existence, his animal and satanic nature. There are two kinds of people, one are those whose Nafs have overcome them and led them to ruin because they yielded to them and obeyed their impulses. The other kinds are those who have overcome their Nafs and made them obey their commands."
When your evil side, bad qualities or your negative self is predominant over your good side, it overshadows, your good actions, that is the stage of the unpurified Nafs. The Nafs n its unrefined state, "the ego (nafs) is the lowest dimension of man's inward existence, his animal and satanic nature." what follows this unpurified Nafs(Ego) is a dirty heart, at this point it is more pleasing and easier to do bad or evil upon yourself and others, doing what you want, and to follow your own passion.
"Verily never will Allah change the condition of a people until they change it themselves (with their own souls)." - Quran 13:11 Surah Ar-Rad(The Thunder)
The unpurified Nafs the ego must be "broken down"
A few ways to break the nafs(ego) is by attacking & humiliating your nafs, pushing yourself, controlling yourself, until you become a new person. A few examples of the characteristic of the nafs is anger, pride, envy, jealousy, lust, backbiting etc...To become a new person, all these bad qualities must be completely destroy, controlled or eliminated, in order to rebuild yourself again.
Sheikh Abdul Qadir Jilani - Quotations on Nafs (The Ego)
At the service of your Nafs your lower self
A certain righteous man is reported as having said: "The hypocrite [munafiq] remains in one and the same spiritual condition for forty years at a stretch, while the champion of truth [siddiq] experiences transformation forty times every single day."
The hypocrite is totally involved with his lower self [nafs], his passions [hawa], his natural inclinations [tab'], his devil [shaitan] and his interest in the things of this world [dunya]. He is committed to their service, from which he never takes a break. He is never known to disagree with their point of view, and he will never say a word to contradict them. His only interests are food and drink, clothes, sexual intercourse and the accumulation of wordly goods, and he does not care how he comes by them. He cultivates his physical body and his worldly affairs, but he lets his heart and his religion [din] go to waste. He tries to please his fellow creatures [khalq], but he gives offense to the Creator [Khaliq].
The longer his hypocrisy [nifaq] continues, the harder and darker his heart becomes, so he is quite unmoved and unaffected by any spiritual counsel [maw'iza], takes no notice of any admonition ['iza], and pays no attention to any reminder. Thus it is undoubtedly a fact that he remains in one and the same spiritual condition for forty years at a stretch.
The champion of truth [siddiq] cannot possibly remain in such a static condition, because he is entirely at the disposal of the Transformer of hearts [Muqallib al-qulub], immersed in the ocean of His power, so that one wave raises him up and another sends him down. He is moved this way and that by the operations [tasarif] and transformations [taqalib] of the Lord of Truth (Almighty and Glorious is He), like a feather in a windswept desert, like a fresh stalk [khama] in the farmer's field, like the corpse in the hands of the ritual washer of the dead [ghasil], like the baby in the hands of the wet nurse [zi'r] or the midwife, like the ball on the receiving end of the polo player's mallet. He has surrendered both his outer [zahir] and his inner being [batin] to Him, and he is completely satisfied with His management. Far from taking any interest in his eating, his sleeping and his carnal appetites, he is interested only in the service of his Lord (Almighty and Glorious is He) and in earning His good pleasure. This is why a certain righteous man once said: "As for the people [of the Lord], their approach to eating is that of the sick, their form of sleep is the sleep of the drowned, and if they speak it is only out of sheer necessity." How could they not be like this? In their hearts there is something that is quite invisible to others. They have ceased to be aware of anything apart from their Lord. They have absented themselves from this world, the hereafter, and everything else apart from Him. They have settled humbly at His door. They have rested their heads on the threshold of His doorway, in readiness to comply with His orders. They have become accustomed to being contented, to needing nothing. Fate and destiny [al-qada' wa 'l-qadar] are now their servants, and these two approach them in visible form and then carry them on their heads.
If you are not one of the people [of the Lord], they are the people you must serve. You must befriend them, sit in their company and draw close to them. Put your material goods at their disposal. Follow them by emulating their actions, not by repeating their words and saying how excellent and wonderful they are. Carry your righteousness [salah] in your heart; do not wear it as part of your outer clothing. Dress as ordinary people dress, but do not behave as they behave.
The Cleaning Of The Heart
The dhikr (remembrance) of Allah being a polish for the heart
Sayyiduna ‘Abdullah ibn ‘Umar (radiyallahu’anhuma) reports that Rasulullah (sallallahu ‘alayhi wasallam) said:
Indeed the hearts rust just as iron does. The Sahabah (radiyallahu’anhum) asked: “What is its polish?”
Sayyiduna ‘Abdullah ibn ‘Umar (radiyallahu ‘anhuma) reports that Rasulullah (sallallahu ‘alayhi wasallam) said:
There is a polish for everything that takes away rust: and the polish for heart is the remembrance of Allah.