Adopted from the book : "The Faith of Shi'a Islam" by : "Allamah Muhammad Ridha al-Muzaffar"
Du'a' is a weapon for the believer, a pillar of din, ad a light of the heaven and the earth.
and here is the truth. It became one of the peculiarities of the Shi'a by which they are distinguished. They have written many books mentioning its importance, and the correct way of performing these supplications, and from these ad'iyah (pl. of du'a) which have been transmitted form the Household, hundreds of books, large and small, have been written, wherein are stored the aims of the prophet and his Household, urging their followers and encouraging them to recite du'a'. From them have been transmitted:
The best worship is du'a'.
The most beloved action in the view of Allah on earth is du'a'.
Du'a' can remove calamities and retribution (which would otherwise have been ordained by Divine decree)
Du'a' is the cure for every sickness.
The first Imam, Amir al-Mu'minin 'Ali (A S) was much given to du'a', and this is clear because he was the leader in monotheism (Sayyid al-muwahhidin) and the Chief among believers (Imam al-alihiyyin) and his ad'iyah and sermons are masterpieces of Arabic eloquence; for instance, the du'a' of Kumayl ibn Ziyad al-Mushhur. And they contain enough Divine and religious education to enable one to tread the right path to being a perfect Muslim.
In fact, the ad'iyah which are transmitted from the Prophet and his Household are the best guidance for a Muslim. When he thinks deeply about them, they will estimate in him strength of faith and belief and the spirit of sacrifice in the path of Allah, and will reveal to him the mystery of worship, and the sweetness of praying to Allah and abandoning everything but Him. They will teach him what is incumbent on a human being to know about his religion, and what will bring him close to Allah, and take him far from corruption his desires and false innovations. In short, in these ad'iyah have been stored the summary of education as regards morality, training of the soul and Islamic beliefs; but they are, at the same time, the most important source of philosophical ideas for investigation theology and for the study of ethics.
If people could follow the guidance contained in the elevation meaning of these ad'iyah- but, alas, they will not be able to so - no trace of the corruption which fills the earth would be found, and those souls which are bound by their sins could go to the Heaven of Truth freely. But it is a near impossibility to pay attention to these reformers who have called humanity to the way of Truth. So the word of Allah has revealed to mankind:
Most surely (man's) soul is wont to command (him to do) evil. (11; 53)
And most men will not believe though you desire it eagerly. (11;103)
The source of badness in man is self-deception and an ignorance of his faults caused by denying theirs existence, thus making them seem good. So he oppresses others, seizes their property, lise, flatters, obeys his own desires, and then deceives himself that he is not really obeying his desires, but that these things need be done, so as to make his sins seem very insignificant. The following transmitted du'a', which takes its strength from Divine revelation, influences man to withdraw himself and to be alone with Allah, and shows him how to confess hi sins and to asking forgiveness form Allah, and reminding himself of his self-deception. Thus the reciter supplicates Allah from the du'a' of kumayl ibn Ziyad;
Would that I knew my Lord, my Master how canst thou being ow Fire on face who fall down in prostration Thy Greatness, or no tongues who speak sincerely of thy Unity and thank thee with their praise, or on hearts who attest to Thy Divinity with certainty,
or on minds who have acquired knowledge of thee to such an extent that they are humbled, or on limbs who have travelled a far to worship Thee obediently and to show their repentance though their submission to Thy Will. We cannot imagine that Thou wilt deal with us thus; this is not what we have been taught of Thy Generosity.
Repeat the recitation of this passage and reflect on the delicateness of the remonstrance, its eloquence and the enchantment of its exposition. At the same time as it inspire the soul to confess its short-coming and its servitude, it also instructs it not to despair of the Mercy and Kindness of Allah. Then it takes to the soul in a clever and subtle manner, and instruct in its highest duties, and make incumbent upon it the thorough performance of these duties. It teaches the soul how man, thorough the performance of its duties, may deserve the granting of forgiveness by Allah, and this is what causes man to listen to his soul and to do what is necessary for him to do, when formerly he was not carrying out his obligations. Then follows another style of remonstrance from the same du'a:
Answer me, O my God, my Master and my Lord!
I may endure They punishment, but how can I endure separation from Thee?
O, answer me,my Lord!
I may endure the heat of Hell, but how can I endure not to look upon Thy Munificence?
This is instruction for the soul in the necessity of taking pleasure in the nearness of Allah, and observing His Kindness and His Power, and loving and desiring what He possesses. Taking pleasure in nearness to Him may reach such a degree that to be without it is worse for the soul than punishment and the heat of Hell. It may be that man can endure the fire of Hell, but he cannot endure to be abandoned. As these passage lead us to understand, love and taking pleasure in closeness to Allah is the best intercession for a guilty person, that Allah may forgive and pardon him. The delicateness of this kind of wonder and adulation of Allah who accepts repentance and forgives sin will not remain unheard.
It would not be a bad thing to end this exposition with a short du'a which lists the highest virtues, and also tells us what is necessary in order that every part and category of humanity may be endowed with the best qualities.
O Lord! Give us steadfastness in obedience and keep us far from sin.
give us sincerity in intention, and knowledge of that which is sacred;
bestow on us guidance and constancy,
seal our tongues with reason and wisdom,
fill our hearts with knowledge and learning,
keep us clean within from what is forbidden and
from those things of which we are uncertain,
keep our hands from oppression and stealing,
hide from our eyes immorality and treachery,
and close our ears to foolish and calumny.
Bestow on our' ulama' freedom concupiscenceand the ability to give good counsel:
and our scholars,application and desire for their studies;
and on those who listen to them, obedience to their spiritual advice.
And on those Muslims who are sick, bestow comfort and cure:
and on our dead, compassion and mercy.
And on our good, dignity and calm,
on our youth acceptance and the true faith and repentance.
And on women, modesty and chastity,
on the rich, humility and generosity,
and on the poor, patience and contendedness.
And on the fighters of for Islam, victory and triumph,
on those who are prisoners of the enemy,
freedom and peace.
And on the rulers, justice and kindness,
and on people they rule, fairness and good behaviour.
And help the pilgrims to Mecca and Holy Shrines to be charitable with their provisions
and their wealth, and help them to perform
what is proscribed for the hajj and the 'ulama.
Grant this thorough Thy Overflowing Generosity and Thy Mercy,
O Merciful and Compassionate!
I recommend you, my brothers, the readers, not to miss the opportunity of reciting these ad'iyah, paying attention to their meaning and their purpose, and thorough presence of mind drawing near and listening to Allah with humility, reading them as if they are speaking of oneself, and following the rites that are proscribed with them by the Household of the Prophet; because reading them mindlessly, merely mouthing the words, will not increase man's knowledge, or cause him to draw near to Allah, none of his troubles will be resolved, and his du'a will not be accepted.
Allah does not accept du'a from a darkened heart, so when you recite a du'a, draw near with your heart and do not doubt that it will be accepted.