[4:43] O you who believe, draw not near to prayer, whilst you are inebriated, until you know what you are saying, nor whilst you are defiled, unless you are traversing a way, until you have washed yourselves. But if you are sick, or on a journey, or if any of you comes from the privy, or you have touched women; and you can find no water, wholesome soil, and wipe your faces and your hands. God is ever Pardoning, Forgiving.
The prohibition against drinks which cause intoxication is not [a prohibition] from prayer. That is to say you should not come to prayer when you are inebriated, so you should avoid drinking that which will intoxicate you. Moreover, when you come to prayer in that condition, the prayer will not be accepted from you.
Intoxication is the loss of mental functioning and awareness, and with it intimate conversation with the Real is not appropriate. The one who is praying speaks intimately with his Lord, so anything which causes the heart to be unmindful of God is included in this by way of allusion and for this reason becomes part of this category. Intoxication is of several types: there is intoxication by wine and intoxication from the heedlessness that comes from being overcome by love for the present world. The most difficult intoxication is your intoxication with your lower self, and it is that which plunges you into separation from Him. If someone is intoxicated from wine, the end of his affair is burning if he is not forgiven. Someone who is intoxicated with himself, his state is separation in the moment from reality. As for the intoxication which the folk allude to, its possessor has his moment protected from it so that he may pray and the matter will be made easy for him. Then when he leaves prayer, it overwhelms him and seizes him [again]. [The intoxication of] those who are not protected in the precepts of the law is mixed with worldly concern.
Nor whilst you are defiled, unless you are traversing a way: He gives permission to those who are compelled to take liberties when crossing through the place of prayer in the state of major ritual impurity, but if one deviates more than is necessary, than one deserves reproof without being excused. It is similar in what occurs with excuses for the time in which obligations are to be performed, and the lifting of the requirement for the performer of the action.
Then verily He (s), by His grace, appointed using clean earth as a substitute for water when there is a lack of it. Similarly, the descent to the plains of separation after reaching the summit of gathering, to the extent which occurs from weakness, is a substitute for the people of realities. And surely the use of clean earth is a substitute for water which is easier to find and of less use in its original form, while the demands made on those who are drawn closer will be more difficult. In the outward sense [of the verse], we are commanded to use earth and in the inward sense to the experience of humility and to perpetual change. Make the act of using earth a diminution and observe in it a protection for your head from the earth and for your feet, for surely glory in the believer - and his Master in deserving Majesty - is more appropriate than the ignominy of his bankrupt state. The bankruptcy of man's works requires his being humble while his knowledge of the Majesty of his Chief causes every kind of being glorified and adorned.