Abdullah b. Mas'ud said in connection with the verse:

" Those whom they call upon, themselves seek the means of access to their Lord," that that verse was revealed in connection with a party of Arabs who used to worship a group amnogst the jinn; the jinn embraced Islam but the people kept worshipping them without being conscious of it. Then this verse was revealed:" Those whom they call upon, themselves seek the means of access to their Lord."

وَحَدَّثَنِي حَجَّاجُ بْنُ الشَّاعِرِ، حَدَّثَنَا عَبْدُ الصَّمَدِ بْنُ عَبْدِ الْوَارِثِ، حَدَّثَنِي أَبِي، حَدَّثَنَا حُسَيْنٌ، عَنْ قَتَادَةَ، عَنْ عَبْدِ اللَّهِ بْنِ مَعْبَدٍ الزِّمَّانِيِّ، عَنْ عَبْدِ اللَّهِ بْنِ عُتْبَةَ، عَنْ عَبْدِ اللَّهِ بْنِ، مَسْعُودٍ ‏{‏ أُولَئِكَ الَّذِينَ يَدْعُونَ يَبْتَغُونَ إِلَى رَبِّهِمُ الْوَسِيلَةَ‏}‏ قَالَ نَزَلَتْ فِي نَفَرٍ مِنَ الْعَرَبِ كَانُوا يَعْبُدُونَ نَفَرًا مِنَ الْجِنِّ فَأَسْلَمَ الْجِنِّيُّونَ وَالإِنْسُ الَّذِينَ كَانُوا يَعْبُدُونَهُمْ لاَ يَشْعُرُونَ فَنَزَلَتْ ‏{‏ أُولَئِكَ الَّذِينَ يَدْعُونَ يَبْتَغُونَ إِلَى رَبِّهِمُ الْوَسِيلَةَ‏}‏