Question
What is the criterion for a clearing of the throat that invalidates the prayer? Is there a relation to opening the mouth during it, or is it sufficient that he cleared his throat and made a sound for the prayer to be invalid? What is the criterion for someone who responds to the Imam when he says: 'Is not Allah the Best of Judges?', and the follower says: 'Yes', or if the follower says: 'Ameen' after 'And grant us victory over the disbelieving people'? And what if someone says 'Astaghfirullah' during the prayer without an excuse, does that invalidate the prayer?
Answer
I say, and with God's help: The prayer is invalidated by clearing the throat with letters if there is no excuse for it, and it is disliked to respond to the imam when he says: "Is not Allah the best of judges?" and others. Seeking forgiveness during the prayer is not part of the prayer's remembrances, so it is disliked. And Allah knows best.