إِنَّ الَّذينَ يَغُضّونَ أَصواتَهُم عِندَ رَسولِ اللَّهِ أُولـٰئِكَ الَّذينَ امتَحَنَ اللَّهُ قُلوبَهُم لِلتَّقوىٰ ۚ لَهُم مَغفِرَةٌ وَأَجرٌ عَظيمٌ

Those who lower their voices in God’s Messenger’s presence are the ones whose hearts have been tested for piety. For them, it is forgiveness and a substantial reward.