"And you do not ask of them any payment for it," meaning: for the Qur'an, so that the burden [of payment] might compel them to abandon it. "It is but a reminder to the worlds," through which they are reminded of Paradise and Hellfire.
﴿وَمَا تَسْأَلُهُمْ عَلَيْهِ مِنْ أَجْرٍ﴾ يَعْنِي: عَلَى الْقُرْآنِ مِنْ أجرٍ، فَيَحْمِلَهُمْ عَلَى تَرْكَهِ الْغُرْمُ ﴿إِنْ هُوَ إِلَّا ذكر للْعَالمين﴾ يذكرُونَ بِهِ الْجنَّة وَالنَّار.
