Fasting: Specifying the Type of Fast in the Intention
Practical Laws of Islam as per the teachings of Ayatullah Sistani
Ruling 1534
If someone wants to keep a qaḍāʾ fast or a fast for recompense (kaffārah), he must specify it. For example, he must make the intention that ‘I am keeping a qaḍāʾ fast’, or ‘I am keeping a kaffārah fast’. However, in the month of Ramadan, it is not necessary for one to make the intention that ‘I am keeping a fast of the month of Ramadan’. In fact, if someone does not know or forgets that it is the month of Ramadan and makes the intention to keep some other fast, it will be considered a fast of the month of Ramadan. Similarly, for a fast of a vow (nadhr) and suchlike, it is not necessary to make the intention to keep a fast of a vow.