Answered by Shaykh Faraz A. Khan
Question: What does the follower of an Imam in salah do when the Imam outpaces his followers(e.g. Follower still in ruku while Imam goes into sajdah)? Does the salah become invalid for the followers?
Answer: Assalamu alaikum wa rahmatullah,
I pray this finds you in the best of health and states.
Following the imam without undue delay is mandatory (wajib), so one must do this even if it entails not finishing a sunna. An example is the 3 tasbihs in ruku or sujud: if one has only done 1 or 2 tasbihs and the imam says “Allahu akbar”, one does not stay to complete the 3, but rather stops and follows the imam.
If, however, following the imam without undue delay entails leaving another mandatory (wajib) element, then one completes that mandatory element before following the imam, despite the delay. An example is if one has not yet finished the tashahhud of the second rak’a in a three or four-rak’a prayer: if the imam rises before the follower has finished the tashahhud, the follower remains sitting and finishes the tashahhud first, and then rises to follow the imam.
[Tahtawi/Shurunbulali, Hashiyat al-Tahtawi ala Maraqi l-Falah]
And Allah knows best.
Faraz A. Khan
Checked & Approved by Faraz Rabbani