وَالنُّطْقُ بِالتَّحْرِيمَةِ بِحَيْثُ يُسْمِعُ نَفْسَهُ عَلَى الْأَصَحِّ
Under the sound position stated here, the able speaker must pronounce the opening Tahrimah audibly enough to hear oneself under normal hearing conditions. Merely thinking the words in the heart is not verbal Tahrimah.
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Prayer Conditions: Time, Intention, and the Opening Tahrimah
وَالنُّطْقُ بِالتَّحْرِيمَةِ بِحَيْثُ يُسْمِعُ نَفْسَهُ عَلَى الْأَصَحِّ
Under the sound position stated here, the able speaker must pronounce the opening Tahrimah audibly enough to hear oneself under normal hearing conditions. Merely thinking the words in the heart is not verbal Tahrimah.