Intention of performing the prayer on time or making up a missed prayer
7-5-2013 | IslamWeb
Question:
What is the religious ruling on making the intention of making up a missed prayer and that of performing a prayer on time? Is the prayer considered invalid if the worshipper does not differentiate between the two intentions while performing the prayer?
Answer:
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 
is His slave and Messenger.
Muslim scholars unanimously agreed that the intention is a condition for the validity of the prayer. Allaah The Exalted Says (what means): {And they were not commanded except to worship Allaah, [being] sincere to Him in religion, inclining to truth, and to establish prayer and to give Zakah. And that is the correct religion.} [Quran 98:5]
The Prophet, sallallaahu ‘alayhi wa sallam, said: "Verily, deeds are based on intentions and an individual is (rewarded) only according to that which he intends." [Al-Bukhari and Muslim]
The place of intention is the heart and not the tongue. Uttering the intention is considered a religious innovation.
The role of intention is to distinguish acts of worship and differentiate between these various acts as well. Prayers in Islam are either obligatory or voluntary. Making an intention is a prerequisite in each obligatory prayer in particular: the worshipper should make an intention to perform a specific prayer; Thuhr, ‘Asr or the like.
Voluntary prayers are divided into two types:
First: Specified voluntary prayers which are performed on certain occasions such as Salatul-Kusoof (i.e. eclipse prayer), Istisqaa’ or rain-invoking prayer, Taraaweeh (i.e. voluntary prayer in Ramadan), Witr and confirmed voluntary prayers. They all require an intention from the worshipper. For instance, if he intends to perform a voluntary prayer for the Thuhr or Maghrib prayer.
Second: General voluntary prayers, such as night prayers, which do not require a specific intention but only the intention of performing prayer.
However, Muslim scholars differed about making an intention while performing obligatory prayers. Is it obligatory to make the intention to perform an obligatory prayer or not? Should the worshipper make an intention to perform a prayer on time if he is praying it on time? Should the worshipper, who is re-offering the obligatory prayer, make the intention of re-offering the prayer or not?
The preponderant opinion among most Muslim jurists is that it is not mandatory for the worshipper to do so. The worshipper may settle for making an intention of performing a specific obligatory prayer. For example, if the ‘Asr prayer is due and the worshipper wants to make up for the Thuhr prayer, which he had missed, he should make the intention of performing the Thuhr prayer and he is not obliged to make the intention of making up for a missed prayer. When he performs the ‘Asr prayer in its due time, he should merely make the intention of performing the ‘Asr prayer and not the intention of performing it at its specific time.
Allaah Knows best.