Silent Dhikr and the Validity of Prayer
Question
If, without moving the lips and tongue, someone performs the wird of “Allah, Allah”, or salawat, or any other of the names of Allah Most High, or recites “astaghfirullah” and the like — is that permissible or not? Can one recite in this manner or not?
Answer
One may indeed recite in this manner as well, but the prayer will not be valid if performed in this way.
Source: Fatawa Mahmudiyya
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