Moderation and uprightness is the health of the self. Straying from moderation and uprightness is a sickness which afflicts the self. Treating the self is similar to treating the body. The body is not created complete and fully grown. It needs training, feeding and exercise in order to reach its potential. Likewise the self - it is created deficient and both in need of and capable of development and completion. Its training is the refinement of character and its nourishment is knowledge.
Similarly, when the body is healthy, the only concern of the physician is to maintain its healthy state. When it is ill, his concern is to seek the return of good health to the body. When the self or character is clean and well-trained and disciplined, one must focus on preserving it and seeking more strength. When it is flawed and lacking in issues of good character, then effort must be made to nourish it, train it and bring it to good character as exemplified in Allah's Messenger (sas) and his Companions (ra).
Ailments of the body are usually treated with their opposites - fever with coolness, cold with warmth, etc. Likewise character flaws which are among the diseases of the heart - its treatment is with its opposite. Ignorance is treated by the seeking of knowledge. Miserliness is treated by acts of generosity. Arrogance is treated by acts of humility. Excessive following of desires is treated by denying the self its desires.
Often, patience is required with the bitterness of the medicine and the denial of desired things in order to cure a body which is ill. Likewise patience and determination is required in the jihad with the self and extended treatments of the illnesses of the heart. In fact they should take a much higher priority since illnesses of the body will end with death while illnesses of the heart are a torment which continues even after death.
When helping yourself or others to refine their character, you should not rush to detailed prescriptions until the problem is first identified. Not everyone requires the same cure. If one is ignorant of the shari'a and the aqidah of Islam, then education and schooling is called for. If there exists a form of arrogance (kibr), then the required training must include acts of humility toward others. If one has excessive anger, then his training must include acts of patience, wisdom and maturity in those same situations which used to arouse his anger.
The greatest need of one who seeks to train and refine his nafs is a strong and sincere intention to do so. If he is hesitant or unsure, success is unlikely. Also, if he doubts his own flaws or enters denial by focusing on greater flaws found in others around him, then success is highly unlikely.
KNOW that every part of the body was created for a specific function. It is known to be "ill" when it is no longer able to fulfill that function or if that function has problems. If the hand is ill, it is unable to strike. If the eye is ill, it becomes difficult to see. The heart is ill when it is difficult for it to fulfill the function for which it was created. That is knowledge, wisdom, consciousness, loving Allah above all else and worshipping Him alone and preferring all of that to every other desire.
So, if one knew "everything" but did not know Allah Most High, it would be just as if he knew nothing at all.
The sign of knowing Allah is love. Whoever knows Allah loves Allah. The sign of love for Allah is that he places NOTHING above or equal to Allah in this love. If anyone places any other object of love equal to or above Allah in their heart, then this heart has become ill. Like a stomach which desires to eat dirt over the eating of bread and loses all desire for healthy food - a stomach which is ill without doubt.
Disease of the heart is subtle and one may not even be aware of it and so people become forgetful and negligent of it. Even if he becomes aware of it, patience and determination with the bitterness of its medicine is difficult - because it conflicts with his desires and drives. Even if he finds in himself strength and patience and a desire for cure, he may fail to find a teacher or guide who will direct him toward his needs or knowledge and direction to get him there. The "doctors" are none other than the scholars and people of knowledge, but these same diseases afflict most of them as well. Who will trust a cure from a "doctor" who is himself ill? For this reason, many Muslims have turned away from these issues entirely, entered denial about the diseases and maladies of the heart and focussed instead on the apparent actions exclusively such as praying and fasting.
Getting back to health means contemplating the flaw itself in order to understand its cure. If he is treating miserliness, its cure is giving up some wealth - but he must not go to excess and reach the level of tabdheer - which itself is another malady. He would be like one who treats cold with excessive heat and brings on another problem. Moderation and equivalency is what is required.
When you want to know the "middle" way, look to your self. If you find that holding on to your wealth and collecting and increasing it is "sweeter" to you and easier than giving it to one who has needs, the the character of miserliness (bukhl) has dominated, so seek a cure in giving. If giving of your wealth becomes easy, so easy that it is at the expense of other valid considerations, then you have gone in the direction of tabdheer and your training should include witholding from spending on some occasions. Continue monitoring yourself in this fashion and examing its reality by what is easy and what is difficult for you until you cut the relationship of your heart to this wealth altogether so that it is not inclined to miserliness nor to excess in giving. When a heart reaches this state, it will go to Allah sound (bi qalbin saleem) with regard to this issue.
It is essential to have a sound heart in such a manner with regard to all issues of character - such that it has no relationship with anything from this world - so that it leaves this world free of all ties to it. In this way, it returns to Allah the return of the "soul at peace" (an-nafs al-mutma'inna).
Since the precise "middle way" between the two extremes is extremely difficult to define and identify like a single hair or the sharp edge of a sword there is no doubt that whoever manages to maintain this balance and this middle way in this life will succeed in the crossing of an equally narrow and difficult path in the hereafter. Because of this difficulty, we say every day many times a day: {Ihdinaa as-siraat al-mustaqeem}. Whoever cannot maintain this absolute balance, let him seek to come as close as possible and salvation and safety is in righteous deeds.
Righteous deeds cannot come about except as a result of good character. So, every Muslim must examine his attributes and his character and busy himself with addressing and curing the flaws he finds. If he only knew the shortness of this life compared to the eternity of the hereafter, he would undertake the difficulty of a few days journey without any hesitation in order to enjoy the bliss in eternity.
KNOW that whenever Allah wishes good for His slave, he give him awareness of his own flaws. One who has true vision does not fail to see his own flaws. Once he knows them, he can seek their cure. Unfortunately, most people are ignorant of their own faults and construct elaborate barriers to prevent them from having to see them - the biggest of which is focusing on the flaws of others. This is the meaning of the advice of the Prophet (sas) to alway look to those better off than yourself in issues of the deen and always look to those les fortunate in issues of this life. One who does so will be recorded with Allah as among the "patient" and the "thankful".
One who wishes to discover his own faults can use the four approaches:
Sit with a teacher or shaikh with humility who can aid him in identifying and addressing his flaws.
Seek a trustworthy, honest and sincere friend and demand of him watchfulness and sincere advice and criticism (nasesha).
Learn is faults from the tongues of his enemies.
Mix up with people and every time you see a bad character in their actions, beware of it in yourself.