Hadith 28-18

حَدَّثَنا أَبي رَضِىَ اللهُ عَنْهُ قالَ: حَدَّثَنا عَلِىِّ بْنِ إِبراهِيمِ بْنِ هاشِم، عَن أَبيهِ، عَن أَحْمَدِ بْنِ عَبْدِاللَّه الخلنجي، عَن أَبي عَلِيِّ الحَسَن بْنِ راشد قالَ سَأَلْتُ الرِّضَا عَلَيْهِ السَّلامُ عَن تَكْبِيرَاتِ الافْتِتَاحِ فَقَالَ سَبْعٌ قُلْتُ رُوِيَ عَنِ النَّبِيِ‏ صَلَّى اللهُ عَلَيْهِ وَآلِهِ أَنَّهُ كَانَ يُكَبِّرُ وَاحِدَةً فَقَالَ إِنَّ النَّبِيَ‏ صَلَّى اللهُ عَلَيْهِ وَآلِهِ كَانَ يُكَبِّرُ وَاحِدَةً يَجْهَرُ بِهَا وَيُسِرُّ سِتّاً.

(The author of the book narrated) my father - may God be pleased with him - narrated that Ali ibn Ibrahim ibn Hashem quoted on the authority of Ahmad ibn Abdullah al-Khalnaji, on the authority of the father of Ali Al-Hassan ibn Rashid, “I asked Al-Ridha’ (a.s.) about the number of times the opening to the call to prayer (Allahu Akbar) must be said. He (a.s.) replied, “It is seven times.” I said, “It has been narrated that God’s Prophet (S) said only one.” The Imam (a.s.) replied, “God’s Prophet (S) said it loudly once and said it quietly the other six times.”