Answered by Shaykh Faraz Rabbani
Is it permissible to sit down and pray the witr prayer? I’m expecting a child and sometimes my back hurts so much I sit and read the sunnahs, is it permissible to do this with the witr?
In general, it is not valid to pray fard and wajib prayers (such as witr) sitting. However, if praying standing causes undue pain that is difficult to bear, or from which actual harm is reasonably feared, then you can pray your witr (and even the fard prayers) sitting. If you can prostrate (on the ground), then pray sitting on the ground in whatever posture you can (with the optimal being normal sitting position in prayer). Otherwise, you could pray with mere head movements.
It is best, however, both because of caution, and as an expression of our love, thankfulness and devotion to Allah to pray standing when able.
Shaykh al-Islam Zakariyya al-Ansari died past the age of 100. His student, Imam Sha`rani reports in his Tabaqat al-Sughra that his teacher would still pray his nafls standing even during his final sickness. He would stay left and right, and endure much pain. When Sha`rani asked him why he did this when Allah did not require him to do so, Shaykh al-Islam replied to the effect that, “My son, the nafs (self) is always inclined towards taking things easy. I fear that if I now give it what it wants, that I may die in a bad state.” Allah be pleased with him.
And Allah alone gives success.