"So when you recite the Quran"—the verse. Al-Hasan said: It was revealed concerning prayer, then it became a sunnah (tradition) outside of prayer; when one intends to recite.
﴿فَإِذا قَرَأت الْقُرْآن﴾ الآيَةَ قَالَ الْحَسَنُ: نَزَلَتْ فِي الصَّلاةِ، ثُمَّ صَارَتْ سُنَّةً فِي غَيْرِ الصَّلاةِ؛ إِذَا أَرَادَ أَنْ يقْرَأ.