(At-twur) 52 : 40
أَمْ تَسْأَلُهُمْ أَجْرًا فَهُمْ مِنْ مَغْرَمٍ مُثْقَلُونَ

Or do you ask them any reward, thus  they are overburdened by debt?

The Messengers and believers neither impose the Lord’s Book Adhikr upon anyone compulsorily and make a burden to him, nor accept any reward from mankind for conveying It. Whoever accepts any type of reward for conveying or teaching the Lord’s Book—such are the disbelievers who prefer this worldly life to the Hereafter. From such transgressing hypocrites who are filling their bellies with fire as explained in verses 2: 174-175, no one will get Guidance. They neither utilize Adhikr themselves, nor give It to others for utilizing as explained in verse 6: 26. Thus, they are hastening the destruction of the universe. See explanation 7: 156-157; 33: 60-61; and 38: 86-87.