What is the ruling on the prayer of one who has obsessive doubts about pronouncing the takbirat (the opening takbir and the takbirat of transition), such that he hears them without the hamza or with a hāʾ instead of an alif, knowing that he hears them correctly when he raises his voice, and that this often happens to him when he is thirsty?

It is clear that the questioner is afflicted with waswas (obsessive whispering) concerning the pronunciation of the takbir (Allahu Akbar) in prayer. The cure for waswas is to disregard it and pay no attention to it. The person afflicted with waswas should pronounce the usual takbir and pay no mind to what Satan deludes him into believing—that he did not perform the takbir correctly. He is not prescribed to perform the prostration of forgetfulness (sujud as-sahw).

Sheikh Abdul Aziz bin Baz said: "The upshot is that when a believing man or woman is afflicted with this matter, they must strive to ask Allah for well-being from it, and frequently seek refuge in Allah from Satan, and be keen to fight against him, not obeying him either in prayer or otherwise. So, if he performs ablution, he should be certain that he has performed ablution and not repeat it. If he prays, he should be certain that he has prayed and not repeat the prayer. If he pronounces the takbir, he should be certain that he has pronounced it and not repeat the takbir, in defiance of and war against the enemy of Allah."

The questioner's prostration of forgetfulness before the taslim does not invalidate his prayer because he did it out of ignorance.