871. hadíth
وَ رَوَى خَالِدُ بْنُ نَجِيحٍ عَنِ اَلصَّادِقِ عَلَيْهِ اَلسَّلاَمُ أَنَّهُ قَالَ: «اَلتَّكْبِيرُ جَزْمٌ فِي اَلْأَذَانِ مَعَ اَلْإِفْصَاحِ بِالْهَاءِ وَ اَلْأَلِفِ.
Khalid ibn Najih narrated from Imam Jafar ibn Muhammad Al-Sadiq (a.s) that He said: "The takbir (saying 'Allahu Akbar') in the adhan must be pronounced firmly, with clear articulation of the 'ha' and 'alif'“.