The Piety forms part of the basic essentials of Islam. It means to observe the Divine Commandments conscientiously and scrupulously and to avoid all forbidden and wicked and shameful things, believing wholly and firmly in the Great Requital of the Last Day and fearing God and His wrath and punishment as a burnt child is supposed to dread the fire. In other words, it demands of us, on the one hand, to carry out, thoroughly and well, the duties prescribed by the Almighty and to fulfill zealously to the Divine law, and, on the other, to refrain strictly from doing anything that has been prohibited us by Him. It calls on us to make the fear of God our constant companion. Both in the Quran and the Traditions a very great emphasis has been laid on piety and righteousness and it has been urged on us most forcefully and persistently to cultivate it in ourselves.

Some of the relevant verses of the Quran are:

O ye who believe! Fear God as He should be feared, and die not except in a state of Islam. (III: 102)
So fear God as much as you can; listen and obey. (LXIV: 16)

O ye who believe! Fear God and let every soul look to what (provisions) he has sent forth for the morrow. Yea, fear God; for God is well-acquainted with (all) that ye do. (LIX: 18)

The Quranic verses, further, reveal that there is a great favour of the Lord even in this world on those who fear God and practice piety and righteousness. God shows special munificence to them and makes His help available to them in a thousand ways: And for those who fear God he (ever) prepares a way out, and He provides for him from (sources) he never could imagine. (XLV: 2-3)

The Quran also tells: that those who lead a life piety and righteousness become ‘Friends of God', and, then, for them there is neither fear nor shall they ever grieve.

Behold! Verily on the Friends of God there is no fear, nor shall they grieve, those who believe and (constantly) guard against evil; for them are Glad Tidings, in the life of the Present and the Hereafter. (X-62-64)

Some of the wonderful boons and blessings that await the pious and the righteous in the Hereafter have been revealed briefly in the following verses:

Say: Shall I give you glad tidings of things far better than those? For the righteous are Gardens in nearness to their Lord, with rivers flowing beneath; therein is their eternal home with Companions (pure and holy), and the good pleasure of God. For in God's sight are (all) His servants.' (III: 15)

And, verily, for the righteous, is a beautiful place of (Final) Return-Gardens of Eternity whose doors will ever be opened to them; therein will they recline (at ease); therein can they call (at pleasure) for fruit in abundance and (delicious) drink; and beside them will be chaste women restraining their glances, (companions) of equal age. Such is the promise made to God for the Day of Account! Truly, such will be Our Bounty (to you) It will never fail. (XXXVIII: 49-54)

In the Quran, again, men of piety are given the very special tidings of place of exceptional nearness to God in the Hereafter: As to the Righteous, they will be in the midst of Gardens and Rivers, in an Assembly of Truth in the presence of a Sovereign Omnipotent. (LIV: 54-55)

The sole criterion of honour and superiority with God is piety.

Verily, the most honoured of you in the sight of God is (he who is) the most righteous of you. (XLIX: 13)
Similarly, it has been declared by the holy Prophet in one of his Traditions that: “Nearest and dearest to me are those who possess the virtue of piety no matter what race or nationality they belong to or which country they live in.”

Piety (i.e., fear of God and an over powering anxiety for the Hereafter) is the root of all virtue. It is the measure of all goodness. We will be as good and noble and as free from what is based on corrupt as there is piety in us.
Another of the Prophet's Traditions reads:

“A holy Companion once said to the Prophet, Sir, I have heard so many of your valuable sayings that I fear I may not be able to remember them all. So I request you for a comprehensive advice, which may suffice for me always. The Prophet replied, ‘Fear God in proportion to your knowledge and make that fear and piety the guiding principles of your life.”

“He who has fear will set out early and he who will set out early will reach the destination in time.”
The fortunate and the successful, indeed, are those who fear God and prepare for the life to come. Even a single tear shed out of fear of God and of His anger and punishment carries a great value in His eyes.

“There are two drops,” says the Prophet, “and two marks than which nothing is more precious to God. Of the two drops so exceedingly dear to Him, one is the tear that may have fallen from the eyes of anyone out of His fear, and the other is the drop of blood that is shed in His path. Similarly, of the two marks one is the mark sustained in the path of God (i.e., the scar left behind by a wound sustained in Jehad), and the other is the mark which may have developed as a result of the carrying out of a religious obligation (as for example, the marks one often sees on the forehead and knees of those who offer the Namaz regularly).”

We will take up one more Tradition of the Prophet. It says: “Never can he go to hell who weeps in the fear of God.”
 
The sum and substance of the entire discussion is that it is great, indeed, to be blessed with true fear of God and a genuine solicitude for the Hereafter. It can literally revolutionize one's whole existence.
 
Brothers, know it thoroughly and well that one who is God fearing in this transitory world will have absolutely nothing to worry in the Hereafter. He will have neither fear nor anxiety. He will dwell in eternal peace, comfort and happiness by the Grace of God. On the contrary, he who is not God fearing and shows no concern for After life and refuses to look beyond the pleasures of material existence for him there will be terrible anguish and distress in the life to come. For thousands of years he will be shedding tears of blood.

The surest way to develop piety, i.e., God fearing-ness and solicitude for the Hereafter is to avail oneself of the company of the devout servants of the Lord who fear Him and obey His commands honestly. Then there are good and reliable religious books, which should be read regularly, and, if a person is illiterate, he should have them read out to him by others. Lastly, it is advisable to meditate in solitude on death and on the rewards one is going to get from God for one's good and virtuous deeds and the punishment that is going to be awarded by Him for one's sins and transgressions against the Divine Law. One should dwell mentally on one's state and visualize what is going to pass in the grave, what will one's condition be when men will be raised up again on the Last Day and produced before God? What will one do when the balance sheet of one's conduct on the earth will be unrolled? Where will one, then, hide one's face?