The Prophet ﷺ told Imran ibn Husayn, who had piles: pray standing; if you cannot, sitting; and if you cannot, on your side. Allah has not placed any hardship on you in the religion (22:78) and does not burden a soul beyond its capacity (2:286).
1The steps of ease
Pray standing if able, even by leaning on a wall or a stick.
If standing is not possible or harms him, pray sitting, and bow and prostrate as he can.
If sitting is not possible, pray on the side, facing the Qibla. If that is not possible, on the back with the feet toward the Qibla.
If bowing and prostrating are not possible, nod with the head, with the prostration lower than the bowing.
If even a nod is not possible, make the movements in the mind. The prayer is not dropped as long as the person is conscious.
2Combining and purification
A sick person who finds that wudu is hard on him may use tayammum.
A sick person who finds it hard to pray each prayer on time may combine Dhuhr with Asr and Maghrib with Isha, according to the Hanbali and Maliki schools.
Where the schools differ
The four Sunni schools agree on the main ruling above and differ in these points. No school is preferred here.
Standing is dropped when it causes real harm or severe pain, or would delay recovery. The schools agree on this. Praying sitting out of laziness, when able to stand, is not valid.
Allah tidak membebani seseorang melainkan sesuai dengan kesanggupannya. Ia mendapat pahala (dari kebajikan) yang diusahakannya dan ia mendapat siksa (dari kejahatan) yang dikerjakannya. (Mereka berdoa): "Ya Tuhan kami, janganlah Engkau hukum kami jika kami lupa atau kami tersalah. Ya Tuhan kami, janganlah Engkau bebankan kepada kami beban yang berat sebagaimana Engkau bebankan kepada orang-orang sebelum kami. Ya Tuhan kami, janganlah Engkau pikulkan kepada kami apa yang tak sanggup kami memikulnya. Beri maaflah kami; ampunilah kami; dan rahmatilah kami. Engkaulah Penolong kami, maka tolonglah kami terhadap kaum yang kafir".
Dan berjihadlah kamu pada jalan Allah dengan jihad yang sebenar-benarnya. Dia telah memilih kamu dan Dia sekali-kali tidak menjadikan untuk kamu dalam agama suatu kesempitan. (Ikutilah) agama orang tuamu Ibrahim. Dia (Allah) telah menamai kamu sekalian orang-orang muslim dari dahulu, dan (begitu pula) dalam (Al Quran) ini, supaya Rasul itu menjadi saksi atas dirimu dan supaya kamu semua menjadi saksi atas segenap manusia, maka dirikanlah sembahyang, tunaikanlah zakat dan berpeganglah kamu pada tali Allah. Dia adalah Pelindungmu, maka Dialah sebaik-baik Pelindung dan sebaik-baik Penolong.
From the Sunnah
Sahih al-Bukhari 1117Authentic collection
The point of the hadith: Pray standing, and if you cannot, sitting, and if you cannot, on your side.
Read the Arabic text
حَدَّثَنَا عَبْدَانُ، عَنْ عَبْدِ اللَّهِ، عَنْ إِبْرَاهِيمَ بْنِ طَهْمَانَ، قَالَ حَدَّثَنِي الْحُسَيْنُ الْمُكْتِبُ، عَنِ ابْنِ بُرَيْدَةَ، عَنْ عِمْرَانَ بْنِ حُصَيْنٍ ـ رضى الله عنه ـ قَالَ كَانَتْ بِي بَوَاسِيرُ فَسَأَلْتُ النَّبِيَّ صلى الله عليه وسلم عَنِ الصَّلاَةِ فَقَالَ " صَلِّ قَائِمًا، فَإِنْ لَمْ تَسْتَطِعْ فَقَاعِدًا، فَإِنْ لَمْ تَسْتَطِعْ فَعَلَى جَنْبٍ ".
This is general information, not a fatwa. For your own situation, ask a qualified scholar.
Fiqh questions
Prayer in illness
The Prophet ﷺ told Imran ibn Husayn, who had piles: pray standing; if you cannot, sitting; and if you cannot, on your side. Allah has not placed any hardship on you in the religion (22:78) and does not burden a soul beyond its capacity (2:286).
Is this a fatwa?
No. It is a summary of well-known rulings with their evidence. For your own case, ask a qualified scholar.
What if my school differs from this answer?
Follow the view of the school you follow and the scholar who teaches you. The page lists the differences of the four schools.