What is the ruling on the tongue stumbling or stopping when uttering "Alhamdulillah Rabbil 'Alamin" (All praise is due to Allah, Lord of the Worlds) in prayer, especially in winter? Is it permissible to complete the rest of the verses silently? Is imamate valid with this problem? And is it permissible to repeat this verse due to the belief that it was pronounced incorrectly?

The questioner is afflicted with waswasah (whispers/obsessive thoughts), and what he complains of is an illusion and imagination stemming from his yielding to these waswasah. He is advised to ignore them and pay no attention to them, and to recite naturally in prayer without affectation. Raising one's voice with a verse, even in a silent prayer, does not affect the validity of the prayer. Likewise, repeating a verse does not affect it, but it is advisable not to repeat it so as not to open the door to waswasah. One must struggle against these illusions.