When and under what circumstances is a Muslim exempt from the obligation of prayer (salat)?

Prayer (salat) is obligatory for every Muslim who is of sound mind and has reached puberty. Anyone who does not meet these conditions is not obliged to perform the prayer. Indeed, the Prophet (peace be upon him) stated in a hadith that accountability is lifted from children and those who are not of sound mind. (Abu Dawud, Hudud, 16 [4398]; Ibn Majah, Talaq, 15 [2041])

In some cases, those with health problems are also exempt from prayer. According to the Hanafi school, a person who is so ill that they cannot even perform prayer by moving only their head is not required to do anything. If such a person dies from this illness, they will meet Allah without any debt for missed prayers, as they had no opportunity to make them up. If they recover and the number of missed prayers does not exceed one day’s (five times) prayers, they must make them up. If the number is greater, according to the sound opinion, they are not required to make them up. The same rulings apply to someone who is unconscious, depending on the duration of unconsciousness. (Kasani, Bada’i, 1/106, 107, 108) Imam Shafi’i stated that if unconsciousness lasts for a full prayer time, making up the missed prayer is not required. (Shirbini, Mughni al-Muhtaj, 1/314)

A person who is bedridden for life, if unable to get up and perform ablution or cannot find someone to help, should perform tayammum (dry ablution) using a brick, tile, or stone kept nearby. If unable to sit up or turn towards the qibla alone, and if there is no one to assist, they should perform the prayer with gestures while lying down, turning their face towards the qibla as much as possible. (Sarakhsi, al-Mabsut, 1/212-213; Kasani, Bada’i, 1/106-107)

If a person is unable to perform tayammum on their own due to illness and cannot find anyone to help, they may consider themselves as having ablution and may either perform the prayer with gestures or postpone it and make it up if they recover. If they do not recover, the obligation is lifted from them. (Ibn Nujaym, al-Bahr, 1/168, 172; Haskafi, al-Durr al-Mukhtar, 39; Ibn Abidin, Radd al-Muhtar, 1/252-253)

Source: T.C. Diyanet İşleri Başkanlığı, Din İşleri Yüksek Kurulu