Language:
كتاب التفسير
65  
Prophetic Commentary on the Qur'an (Tafseer of the Prophet (pbuh))
(14)
"...And offer your Salāt (prayer) neither aloud nor in a low voice..." (V.17:110)
(14)
Sahih al-Bukhari 4723

Narrated Aisha:

The (above) verse was revealed in connection with the invocations.

حَدَّثَنِي طَلْقُ بْنُ غَنَّامٍ، حَدَّثَنَا زَائِدَةُ، عَنْ هِشَامٍ، عَنْ أَبِيهِ، عَنْ عَائِشَةَ ـ رضى الله عنها ـ قَالَتْ أُنْزِلَ ذَلِكَ فِي الدُّعَاءِ‏.‏
Reference : Sahih al-Bukhari 4723
In-book reference : Book 65, Hadith 245
USC-MSA web (English) reference : Vol. 6, Book 60, Hadith 247
  (deprecated numbering scheme)