SHAFAQNA- Know that the intention (niyah) is to decide or to determine to do something. It is the soul’s decision on performing some act after conceiving it and then acknowledging its advantage and judging its necessity. It is a psychological and conscientious condition, which appears after the said procedures. It is, then, expressed as to be a decision, a determination, a want, a will, an objective and the like. It appears in all voluntary actions, as there can be no voluntary act without undergoing the said process, and it is there in the entire action, in reality, not allegorically. It does not need, however, that the details should be in the mind from the very beginning or even during the process, nor should one necessarily imagine the objective and the decision in detail. It sometimes happens that man does the act according to a decision, and yet he is completely unaware of the detailed picture of the act and the decision, while the fact is there, and it takes place in the outside motivated by that fact. This is quite consciously obvious in the voluntary acts.
Nevertheless, the whisperings of the wicked Satan and the sporting of fancy overrule reason and disguise the necessities in the eyes of the helpless man, and man, instead of spending his precious life in improving and purifying his deeds, and in freeing them from internal evils, and instead of spending it in acquiring monotheistic knowledge, godliness and being in quest of Allah, the vile Satan whispers in his ears and induces him to spend only half of his life in quest of a necessary and obligatory matter.
Satan’s snares and artifices are too many: one may be induced by him to give up the act altogether, while the other whom he despairs of inducing to drop the act, induces him to commit other follies, such as self-conceitedness and hypocrisy. If Satan could not succeed in this, he would try to falsify one’s worship by way of causing him to pretend holiness: by slighting the worships of the people in his eyes, and by causing him to regard the people indifferent \[heedless]. Then he induces him to spend all his life on matters such as the niyah , which is inseparable from the act , or the takbir or the recitation , which are common and ordinary acts .At any rate , Satan would not leave man alone before nullifying his worship by one way or another.
Satanic whisperings come through diverse ways, which we cannot discuss for the time being, nor scrutinize them all. Nevertheless, the whispering in the niyah, from among them, may be the most ridiculous and the strangest, because if someone tried, with all his powers, to do a voluntary act in all his life, without a niyah \[an intention], it would be impossible for him to do it. Nevertheless, you may find some wretched, sick and feeble-minded person who spends a considerable time at every salat just to have a firm intention.
Such a person is more like the one who thinks a long time whether he is to decide to go shopping or to go for a lunch. This helpless man, to whom the salat should be his ascension to His proximity, and the key to his happiness, and, by applying its cordial disciplines and realizing the secrets of this divine grace he should perfect his essence \[dhat] and secure his growth \[nash’ah] of life, he, on the contrary, neglects all these matters, or, much worse, besides regarding them unnecessary, he takes them all to be false, and uses his dear and valuable capital to serve Satan and to obey his slinking whispers, placing the God-given reason \[`aql], which is the light of guidance, under the rule of Iblis.
‘ By: Imam Khomeini, Adabus-Salat; The Disciplines of the Prayer, p.251-253