"And do not hasten with the Qur'an before its revelation is completed for you," meaning: do not recite it until We have finished it for you. When revelation would descend upon the Prophet, he would recite it and exert himself in it, for fear that he might forget it.
﴿وَلا تَعْجَلْ بِالْقُرْآنِ مِنْ قَبْلِ أَن يقْضى إِلَيْك وحيه﴾ أَيْ: لَا تَتْلُهُ؛ حَتَّى نُتِمَّهُ لَكَ؛ كَانَ النَّبِيُّ إِذَا نَزَلَ عَلَيْهِ الْوَحْيُ يَقْرَؤُهُ وَيُدْئِبُ فِيهِ نَفسه؛ مَخَافَة أَن ينسى
