وَلَوِ اتَّبَعَ الْحَقُّ أَهْوَاءهُمْ لَفَسَدَتِ السَّمَاوَاتُ وَالاَْرْضُ وَمَن فِيهِنَّ
And if Al-Haqq had followed their desires, verily, the heavens and the earth, and whosoever is therein would have been corrupted!
Mujahid, Abu Salih and As-Suddi said,
"Al-Haqq is Allah, may He be glorified."
What is meant by the Ayah is that if Allah had responded to the desires in their hearts and prescribed things accordingly, the heavens and the earth and whosoever is therein, would have been corrupted, i.e., because of their corrupt and inconsistent desires.
As Allah says of them elsewhere;
لَوْلَا نُزِّلَ هَـذَا الْقُرْءَانُ عَلَى رَجُلٍ مِّنَ الْقَرْيَتَيْنِ عَظِيمٍ
"Why is not this Qur'an sent down to some great man of the two towns!" (43;31)
Then He says;
أَهُمْ يَقْسِمُونَ رَحْمَةَ رَبِّكَ
Is it they who would portion out the mercy of your Lord! (43;32)
And Allah says;
قُل لَّوْ أَنتُمْ تَمْلِكُونَ خَزَايِنَ رَحْمَةِ رَبِّى إِذًا لامْسَكْتُمْ خَشْيَةَ الاِنفَاقِ
Say;"If you possessed the treasure of the mercy of my Lord, then you would surely hold back for fear of spending it." (17;100)
أَمْ لَهُمْ نَصِيبٌ مِّنَ الْمُلْكِ فَإِذاً لاَّ يُوْتُونَ النَّاسَ نَقِيراً
Or have they a share in the dominion! Then in that case they would not give mankind even a Naqir. (4;53)
All of this goes to show how incapable mankind is and how divergent and inconsistent their ideas and desires are. Only Allah, may He be glorified, is Perfect in all His attributes, words, actions, laws, power and control of His creation, may He be exalted and sanctified. There is no God but He and no Lord besides Him.
Then He says;
بَلْ أَتَيْنَاهُم بِذِكْرِهِمْ
Nay, We have brought them their reminder,
meaning the Qur'an,
فَهُمْ عَن ذِكْرِهِم مُّعْرِضُونَ
but they turn away from their reminder.
The Prophet does not ask for any payment, and he calls to the straight path
Allah says