The Messenger of Allāh, peace and blessings be upon him, said:
مَثَلُ الَّذِي يَقْرَأُ الْقُرْآنَ وَهُوَ حَافِظٌ لَهُ مَعَ السَّفَرَةِ الْكِرَامِ الْبَرَرَةِ وَمَثَلُ الَّذِي يَقْرَأُ وَهُوَ يَتَعَاهَدُهُ وَهُوَ عَلَيْهِ شَدِيدٌ فَلَهُ أَجْرَانِ
The example of those who recite the Quran and memorize it is that of one who is with the ‘righteous and noble scribes’ (80:15); and the example of one who recites the Quran with great difficulty is that of one who receives a double reward.
[Sahih Bukharee 4653]