signs, symptoms and cures of the spiritual diseases of the heart
As for action that is beneficial in purifying the heart, none is more effective than what is consistent, even if it is slight.
Include also action that is done in the absence of witnesses, or action done purely for His love or out of awe of His majesty.
The purest deed is that done by someone free of worldly wants. The opposite of this is the deed of the covetous one whose endeavors are ultimately insignificant.
The actions of those who strive out of hope are more resplendent and exalted than one whose striving is compelled by fear.
"Purification" is not a state, but an ongoing process. Just as we go through a day careful about our bodily cleanliness, we must similarly tend to our spiritual purity, for purification and sincerity do not survive a passive relationship. Left unattended, the heart becomes encrusted. Unwholesome deeds accumulate and take away its purity.
Scholars have commented that when the Prophet's Companions took on supererogatory rites of worship (nawa̅fil), they did so for the duration of their lives. It was something they embraced as a spiritual practice, and they did not abandon it. This is not to say that this is an obligation.
The Prophet ﷺ was a universal prophet, which means, among other things, that he was an example for all people. He fasted and broke his fasts. He prayed and rested. The life of Prophet ﷺ has something for people of diverse strengths and weaknesses—for everyone. For example, God opens the hearts of some people so that they incline to perform night prayer. For others, He opens their hearts to recitation of the Qur'an. For others yet, it may be that they are inclined towards being generous. Others may find their hearts inclining towards consistent remembrance of God. Fasting is the love and passion of some people. And others love memorizing hadith and teaching it.There is much in Islam and in the beautiful model of the Prophet ﷺ that one may learn from. Very rarely do we find a person who encompasses all (or even most) of his qualities. However, if a person finds himself inclining to a certain supererogatory worship rite, he should follow it and remain consistent in its practice.
Of particular benefit is that which extends beyond the individual or is difficult for the self—such as a glutton's fast,
Or the years of youth spent in avoiding wrongs and in willing obedience, or the contributions of a miser from the best of his wealth when he is of sound mind, seeking thereby the pleasure of God with absolute sincerity.
All of these purify the heart. Moreover, doing a good deed which one conceals is also purifying; and the best of endeavors is one that purifies the heart.
Likewise, the most harmful of wrongs is what hardens the heart and was done with consistency or [the doer] taking joy in doing it. Sages have preferred a wrong that engenders humility to a right that clothes one in a gown of self-righteous arrogance.
An atom's weight of exalted praiseworthy action from the heart—like contentment with what one has, detachment from worldly things, and reliance [upon God]—
Is better in God's sight than high mountains of external actions [without sincerity].
Indeed, leaving a dollar because it is from a prohibited source is better than giving much in charity and [better than] several pilgrimages.
The Imam advises also to seek out acts that are trying to the soul. The Prophet ﷺ said that the best charity is charity given when one is in good health and sound condition and fears poverty. Thus, the miser should give to cleanse his heart of miserliness; and the fear of poverty should not prevent him from giving.
An abominable attitude somehow survives in some parts of the Muslim world. It basically states that the year of responsibility is age forty, and that before that age, one may do as he wills. This is based on the fact that the Prophet ﷺ received revelation at that age. However, this idea is entirely ignorant and vacuous. It is also morally and spiritually devastating. Who can guarantee lengthy life? And who can guarantee one will actually turn to repentance after years of disobedience? To intentionally wreak moral havoc in anticipation of repenting late is untenable.
The Imam says next that the worst things a person can do are those acts that harden the heart. One of them is speaking a lot without mentioning God. The more the tongue is occupied in remembering God, the softer the heart becomes—imbued with compassion, mercy, and love.
"The best actions are the continuous ones, even if they are slight" (The Prophet ﷺ).
"Do not sit in a gathering without mentioning God, for a gathering in which God is not mentioned will harden the heart" (Jesus, peace be upon him).
"Leaving one penny from what God has made forbidden is better than going to pilgrimage 70,000 times" (Imam Saḥnu̅n).