Every muscle in the body was created to execute a specific function, by which, it can obtain the pinnacle of its performance. And the sickness of that particular body part is its failure to execute the function for which it was created or having some level of deficiency in performing it, if it even functions at all.
The sickness of the hand is its inability to grab or clutch. The sickness of the eye is its inability to see or observe. The sickness of the tongue is its inability to utter. The sickness of the body is its inability to move in the natural order it was created to or its deficiency in doing do. The sickness of the heart is its inability to execute the functions it was created to perform such as: being conscious of Allah, knowing Allah, loving Allah, desiring to meet Allah and turning constantly towards Him, while giving precedence to this over the heart’s every ardent desire.
Consequently, if the slave knows everything else but fails to know Allah, it is as if he knows absolutely nothing. Even if he achieves some share or portion of what this transient life has to offer (from its many pleasures and desires) but fails to develop a solid intimate relationship with Allah which produces an ardent desire to meet Him emerging from a strong love of Him, then he has failed to achieve the bliss this life has to offer as well as forfeited the ultimate pleasure of his eye.
Rather if the heart is completely void of the knowledge of Allah and the desire to meet Him, then all of what he obtained from the pleasures and delights of this life will inevitably become a punishment for him.
Thus he becomes a punisher of his own self, with the same exact thing he thought he was granting himself happiness and pleasure with. And this is from two angles:
The First: Because of the sorrow and grief that resulted from his forfeiture and his desire of the transient things of this life, it became a barrier between him and obtaining what his soul was utterly attached to.
The Second: Because he forfeited what was better, more beneficial and longer lasting for him, in that he never achieved it.
Hence, the beloved thing he attained was actually forfeited and the more beloved thing was never even achieved.
Everyone who truly knows Allah loves Him and devotes his worship to Him sincerely and completely and does not give precedence to the other things that are beloved to him over Allah.
And whoever does so, his heart is truly sick. Similar to the intestines of the human being, if it gives precedence to unhealthy food over food that is healthy, it loses its desire for the food that is actually healthy and accustoms itself to the unhealthy food.
It is possible for the heart to become sick, and the sickness will continue to increase while the individual does not even realize it, due to his preoccupation and negligence regarding its well-being and the means by which this well-being is acquired.
Rather the heart can die while the individual is not even aware of its demise. The indication that the heart is sick is that it is not affected by the injurious nature of evil, not bothered by the fact that it is ignorant of the haqq (i.e. truth), and its beliefs are flawed.
The heart that is full of life is affected by the injurious nature of evil and harmed by its ignorance of the truth based upon the extent of its life. But It is possible that the individual can recognize the sickness of his heart, however, tolerating the bitterness of the medicine to cure it could be just as painful as the sickness itself.
Thus he gives precedence to the continuity of the sickness over the difficulties found in the remedy because the remedy actually opposes his desires and this is the most difficult thing for the soul but there is nothing more beneficial for it.
At times the individual accustoms himself to patience then it dissolves and his steadfastness weakens and eventually subsides due to his lack of knowledge, foresight and impatience, like a person who traverses upon a frightening path that actually leads to safety and security. And he knows that if he exerts patience the fear will subside and he will attain the safety and security he desires.
Nonetheless, he is in dire need of unyielding perseverance and certainty about the path upon which he is traversing. And whenever his patience and certainty weakens he will turn back from the path and will not be able to endure the difficulties of it, especially if he is alone without a companion to traverse this path with him. He will begin to say: “Where did all the people go? I need someone to emulate!”
This is the state of most people and is also the main component of their destruction. So the one who is truly knowledgeable, never feels alienated because there is a lack of camaraderie upon the path he is traversing or because he was abandoned, especially when his heart recognizes that it has a camaraderie with the foremost generation, those upon whom Allah has bestowed His bounty upon from the prophets, the truthful, the martyrs and the righteous, and how great is the company of these individuals.
Ishaaq Ibn Ra’huyah (Rahimahullah), one of the contemporaries of Imam Ahmad, was asked about an issue and when he replied to it, someone said to him: “Your brother Ahmad Ibn Hanbal was asked the same question and responded with the same reply as you did!”
So Ishaaq said: “I did not think anyone would agree with me in this issue!“
Therefore the ability of the slave to traverse this path alone in search of his success is, in itself, proof of the sincerity in his quest.
Thus Ishaaq did not feel alienated because no one agreed with him about the matter, even before the truth of the matter became apparent to everyone else and this is because, when the truth becomes apparent, it is not in need of anyone to testify on its behalf.
For the heart can see the truth just as the eye can see the sun. If the individual sees the sun with his own eyes his knowledge and belief regarding it, is not in need of anyone testifying or agreeing to the confirmation of its rising.
Source: Ighatha tul Lahfan min Masa’id ush Shatan, Vol.1, Page 68 by Ibn al-Qayyim