Assalaamu alaykum. Please answer me directly; I would be grateful to you! Does the intention depend on supplication? Do we get the reward by saying 'In Shaa Allaah' (if Allaah wills) while not having any intention to do it, or supplicating without having the intention to do so? Can these things be accepted by Allaah without holding an intention, like praying without an intention? Is having the intention necessary?

All perfect praise be to Allaah, The Lord of the worlds. I testify that there is none worthy of worship except Allaah and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.

The intention is the purpose behind doing something. If you mean that the person makes the supplication without having the intention to supplicate Allaah, then it is inconceivable that any sane person would do such a thing. Shaykhul-Islam Ibn Taymiyyah said, "The intention is consequent to knowledge. When one knows what he wants to do, he necessarily intends it. Whenever the person knows the act that he is performing, he has essentially held the intention to perform it. It is inconceivable that one would know the act that he is carrying out without holding the intention to perform it!"

Shaykh Ibn ‘Uthaymeen wrote, "It is deduced from the hadeeth that reads, 'Deeds are by the intentions' that all deeds should have intentions because any sane person would not carry out a deed without holding the intention of performing it. Some scholars even said, 'If Allaah had enjoined us to do a deed without an intention, it would have been an obligation beyond our ability." [Sharh Al-Arba‘een An-Nawawiyyah]

However, if you mean that the person supplicates Allaah with an inattentive heart, and you ask whether Allaah accepts the supplications of a person offering supplication whilst he is unfocused or absent-minded, then you should know that the Prophet, sallallaahu ‘alayhi wa sallam, said, "Call upon Allaah while being certain of being answered, and know that Allaah does not respond to a supplication from the heart of one who is heedless and occupied by play." [Ahmad, Al-Haakim, and At-Tirmithi]

Moreover, it has been narrated in a Mawqoof report (stopped at the level of the Companion) on the authority of ‘Abdullaah ibn Mas‘ood that he said, "Allaah does not answer the supplication of a person who is showing off and wants to be heard or seen by others (to win their admiration and have his deeds widely publicized) or of someone whose heart is preoccupied with play; He only answers the supplications of the attentive heart." [Al-Bukhari in Al-Adab Al-Mufrad]

It is not prescribed for the person supplicating his Lord to say "In Shaa Allaah" in the supplication. The Prophet, sallallaahu ‘alayhi wa sallam, said, "None of you should say, 'O Allaah! Forgive me if You will,' or, 'Bestow Your Mercy on me if You will,' or, 'Provide me with means of subsistence if You will,' but he should be firm in his request, for Allaah does what He wills, and nobody can force Him (to do anything)." [Al-Bukhari and Muslim]

You asked about supplicating without the intention; if you mean asking whether the intention is a condition for the acceptance of supplication or not, then you should know that all acts of worship are invalid without the intention. If a person performs the acts and movements of the prayer without holding the intention of offering the prayer, then this is not sufficient in terms of clearing himself of his liability from the obligation. The same applies if the person gives money to the poor without holding the intention of paying zakah; this is not sufficient in terms of clearing himself of his liability from the obligation of zakah. Similarly, if the person raises his hands and supplicates without holding the intention of imploring Allaah, then it does not count as invoking Allaah, like someone, for example, reciting supplications only to teach a young child.

As for your question as to whether the person needs to hold an intention for all acts, then you should know that the Muslim is enjoined to invoke the intention for all acts of worship such as prayer, zakah and fasting, obligatory and voluntary alike. The Maaliki scholar Al-Walaati wrote, "Intention is a condition for the validity of acts of worship, and it is a prerequisite for earning rewards for any good deed. The Prophet, sallallaahu ‘alayhi wa sallam, said, 'The reward of deeds depend upon the intentions, and every person will get the reward according to what he has intended.'" [Qawaa'id Al-Mathhab Al-Maaliki]

It should be noted, though, that some obligatory acts do not require invoking the intention, such as the removal of impurities, fulfilling the rights of others, settling grievances and injustice, providing for one's dependents, and the like. However, the doer does not earn rewards for doing such acts as righteous deeds without invoking a good intention for doing them. Performing any righteous deed for the purpose of drawing closer to Allaah, even if it is not obligatory or falls into the category of normal worldly acts such as eating and drinking and the like, yields no rewards unless he performs it with the intention of drawing closer to Allaah, The Exalted.

Allaah knows best.