Answered by Shaykh Faraz Rabbani
If one makes mistake while reciting the quran in a fard salah is his salah invalidated?
Walaikum assalam,
It depends on the nature of the mistake. If it is a major mistake that completely changes the meaning of verse, and is not a common mistake in pronunciation or a mistake in grammar (such mistakes are ignored), then the prayer would be invalidated.
Common mistakes in pronunciation, and all mistakes in grammar are excused, unless done willfully and intentionally.
And Allah knows best.
Wassalam,
Faraz Rabbani.