Musnad Ahmad 155
It was narrated that Ibn 'Abbas said:
This verse was revealed when the Messenger of Allah ﷺ was preaching secretly in Makkah: ` And offer your Salah neither aloud nor in a low voice` [Al Isra' 17:110]. He said: When he led the companions in prayer, he raised his voice reciting the Qur'an, and when the mushrikeen heard that, they reviled the Qur'an, the one who revealed it and the one to whom it was sent. Then Allah said to his Prophet: ` And offer your Salah (prayer) neither aloud` i.e, when reciting, lest the mushrikeen hear and revile the Qur'an,`nor in a low voice` that your companions cannot hear the Qur'an, so that they can learn it from you; `but follow a way between`
حَدَّثَنَا هُشَيْمٌ، أَنْبَأَنَا أَبُو بِشْرٍ، عَنْ سَعِيدِ بْنِ جُبَيْرٍ، عَنِ ابْنِ عَبَّاسٍ، قَالَ نَزَلَتْ هَذِهِ الْآيَةُ وَرَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ مُتَوَارٍ بِمَكَّةَ ‏{‏وَلَا تَجْهَرْ بِصَلَاتِكَ وَلَا تُخَافِتْ بِهَا‏}‏ قَالَ كَانَ إِذَا صَلَّى بِأَصْحَابِهِ رَفَعَ صَوْتَهُ بِالْقُرْآنِ قَالَ فَلَمَّا سَمِعَ ذَلِكَ الْمُشْرِكُونَ سَبُّوا الْقُرْآنَ وَمَنْ أَنْزَلَهُ وَمَنْ جَاءَ بِهِ فَقَالَ اللَّهُ عَزَّ وَجَلَّ لِنَبِيِّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ ‏{‏وَلَا تَجْهَرْ بِصَلَاتِكَ‏}‏ أَيْ بِقِرَاءَتِكَ فَيَسْمَعَ الْمُشْرِكُونَ فَيَسُبُّوا الْقُرْآنَ ‏{‏وَلَا تُخَافِتْ بِهَا‏}‏ عَنْ أَصْحَابِكَ فَلَا تُسْمِعُهُمْ الْقُرْآنَ حَتَّى يَأْخُذُوهُ عَنْكَ وَابْتَغِ بَيْنَ ذَلِكَ سَبِيلًا‏.‏