Awesome Article on the Heart Masha'Allah

Purification of the Heart
From the works of Ibn Rajab al-Hanbali, Ibn al-Qayyim al-Jawziyya, and Imam Ghazali
Types of Hearts
Just as the heart may be described in terms of being alive or dead, it may also be regarded as belonging to one of three types; these are the healthy heart, the dead heart, and the sick heart.
The Healthy Heart
On the Day of Resurrection, only those who come to Allah with a healthy heart will be saved. Allah says: "The day on which neither wealth nor sons will be of any use, except for whoever brings to Allah a sound heart. (26:88-89)"
In defining the healthy heart, the following has been said: "It is a heart cleansed from any passion that challenges what Allah commands, or disputes what He forbids. It is free from any impulses which contradict His good. As a result, it is safeguarded against the worship of anything other than Him, and seeks the judgment of no other except that of His Messenger (s). Its services are exclusively reserved for Allah, willingly and lovingly, with total reliance, relating all matters to Him, in fear, hope and sincere dedication. When it loves, its love is in the way of Allah. If it detests, it detests in the light of what He detests. When it gives, it gives for Allah. If it withholds, it withholds for Allah. Nevertheless, all this will not suffice for its salvation until it is free from following, or taking as its guide, anyone other than His Messenger (s). Those who follow the Prophet (s) in observing his Sunnah and the Shari`ah are guides to those who had not met him (s).
A servant with a healthy heart must dedicate it to its journey's end and must not give precedence to any other faith or words or deeds over those of Allah and His Messenger, may Allah bless him and grant him peace and those who are rightly guided, keeping the Prophetic example. Allah says:
"Oh you who believe, do not put yourselves above Allah and His Messenger, but fear Allah, for Allah is Hearing, Knowing. (49:1)"
The Dead Heart
This is the opposite of the healthy heart. It does not know its Lord and does not worship Him as He commands, in the way which He likes, and with which He is pleased. It clings instead to its lusts and desires, even if these are likely to incur Allah's displeasure and wrath. It worships things other than Allah, and its loves and its hatreds, and its giving and its withholding, arise from its whims, which are of paramount importance to it and preferred above the pleasure of Allah. Its whims are its imam. Its lust is its guide. Its ignorance is its leader. Its crude impulses are its impetus. It is immersed in its concern with worldly objectives. It is drunk with its own fancies and its love for hasty, fleeting pleasures.
It is called to Allah and the akhira from a distance but it does not respond to advice, and instead it follows any scheming, cunning shaytan. Life angers and pleases it, and passion makes it deaf and blind1 to anything except what is evil.
To associate and keep company with the owner of such a heart is to tempt illness: living with him is like taking poison, and befriending him means utter destruction.
The Sick Heart
This is a heart with life in it, as well as illness. The former sustains it at one moment, the latter at another, and it follows whichever one of the two manages to dominate it. It has love for Allah, faith in Him, sincerity towards Him, and reliance upon Him, and these are what give it life. It also has a craving for lust and pleasure, and prefers them and strives to experience them. It is full of self-admiration, which can lead to its own destruction. It listens to two callers: one calling it to Allah and His Prophet (s) and the afterlife (akhira); and the other calling it to the fleeting pleasures of this world. It responds to whichever one of the two happens to have most influence over it at the time.
The first heart is alive, submitted to Allah, humble, sensitive and aware; the second is brittle and dead; the third wavers between either its safety or its ruin.

Symptoms Of the Heart's Sickness and Signs of Its Health
"He it is Who sent down calmness and tranquillity into the hearts of the believers, that they may grow more in Faith along with their (present) Faith. And to Allah belong the hosts of the heavens and the earth, and Allah is Ever Al-Knower, All-Wise." The Holy Quran: 48:4
Four-Symptoms Of the Heart's Sickness and Signs of Its Health
The Signs of a Sick Heart
A servant's heart may be ill, and seriously deteriorating, while he remains oblivious of its condition. It may even die without him realising it. The symptoms of its sickness, or the signs of its death, are that its owner is not aware of the harm that results from the damage caused by wrong actions, and is unperturbed by his ignorance of the truth or by his false beliefs.
Since the living heart experiences pain as a result of any ugliness that it encounters and through its recognising its ignorance of the truth (to a degree that corresponds to its level of awareness), it is capable of recognising the onset of decay-and the increase in the severity of the remedy that will be needed to stop it-but then sometimes it prefers to put up with the pain rather than undergo the arduous trial of the cure!
Some of the many signs of the heart's sickness if its turning away from good foods to harmful ones, from good remedies to shameful sickness. The healthy heart prefers what is beneficial and healing to what is harmful and damaging; the sick heart prefers the opposite. The most beneficial sustenance for the heart is faith and the best medicine is the Qur'an.
The Signs of a Healthy Heart
For the heart to be healthy it should depart from this life and arrive in the next, and then settle there as if it were one of its people; it only came to this life as a passer-by, taking whatever provisions it needed and then returning home. As the Prophet, may Allah bless him and grant him peace, said to Abdullah ibn Umar, "Be in this world as if you were a stranger or a passer-by."2 The more diseased the heart is, the more it desires this world; it dwells in it until it becomes like one of its people.
The healthy heart continues to trouble its owner until he returns to Allah, and is at peace with Him, and reaches Him, like a lover driven by compulsion who finally reaches his beloved. Besides his love for Him he needs no other, and after invoking Him no other invocations are needed. Serving Him precludes the need to serve any other.
If this heart misses its share of reciting the Qur'an and invoking Allah (dhikrullah), or completing one of the prescribed acts of worship, then its owner suffers more distress than a cautious man who suffers because of the loss of money or a missed opportunity to make it. It longs to serve, just as a famished person longs for food and drink.
Yahya ibn Mu'adh said:
Whoever is pleased with serving Allah, everything will be pleased to serve him; and whoever finds pleasure in contemplating Allah, all the people will find pleasure in contemplating him.
This heart has only one concern: that all its actions, and its inner thoughts and utterances, are obedient to Allah. It is more careful with its time than the meanest people are with their money, so that it will not be spent wastefully. When it enters into the prayer, all its worldly worries and anxieties vanish and it finds its comfort and bliss in adoring its Lord. It does not cease to mention Allah, nor tire of serving Him, and it finds intimate company with no-one save a person who guides it to Allah and reminds it to Him.
Its attention to the correctness of its action is greater than its attention to the action itself. It is scrupulous in making sure that the intentions behind its actions are sincere and pure and that they result in good deeds.
As well as and in spite of all this, it not only testifies to the generosity of Allah in giving it the opportunity to carry out such actions, but also testifies to its own imperfection and shortcomings in executing them.
The Causes of Sickness of the Heart
The temptations to which the heart is exposed are what cause its sickness. These are the temptations of desires and fancies. The former cause intentions and the will to be corrupted, and the latter cause knowledge and belief to falter.
Hudhayfa ibn al-Yamani, may Allah be pleased with him, said:
The Messenger of Allah (s) said, "Temptations are presented to the heart, one by one. Any heart that accepts them will be left with a black stain, but any heart that rejects them will be left with a mark of purity, so that hearts are of two types: a dark heart that has turned away and become like an overturned vessel, and a pure heart that will never be harmed by temptation for as long as the earth and the heavens exist. The dark heart only recognises good and denounces evil when this suits its desires and whims.3
He, may Allah bless him and grant him peace, placed hearts, when exposed to temptation, into two categories:
First, a heart which, when it is exposed to temptation, absorbs it like a sponge that soaks up water, leaving a black stain in it. It continues to absorb each temptation that is offered to it until it is darkened and corrupted, which is what he meant by "like an overturned vessel". When this happens, two dangerous sicknesses take hold of it and plunge it into ruin:
The first is that of its confusing good with evil, to such an extent that it does not recognise the former and does not denounce the latter. This sickness may even gain hold of it to such an extent that it believes good to be evil and vice-versa, the Sunnah to be bida' and vice-versa, the truth to be false and falsity to be the truth.
The second is that of its setting up its desires as its judge, over and above what the Prophet (s) taught, so that it is enslaved and led by its whims and fancies.
Second, a pure heart which the light of faith is bright and from which its radiance shines. When temptation is presented to pure hearts such this, they oppose it and reject it, and so their light and illumination only increase.
NOTES:
1. It has been related on the authority of Abu'd-Darda' that the Messenger of Allah, may Allah bless him and grant him peace, said, "Your love for something that makes you blind and deaf." Abu Daw'ud, al-Adab, 14/38; Ahmad, al-Musnad, 5/194. The hadith is classified as hasan.
2. Sahih Al-Bukhari, Kitab ar-Riqaq, 11/233.
3. Sahih Muslim, Kitab al-Iman, 2/170 (with different wording).