(And among mankind is he who disputes about Allah, without knowledge, and follows every rebellious Shaytan.) And here He tells us about those who call others to misguidance, the leaders of disbelief and innovation:
(And among men is he who disputes about Allah, without knowledge or guidance, or a Book giving light (from Allah).) meaning, with no correct rational thought, and no clear transmitted text; what they say is based only on their opinions and whims. Allah's saying,
ثَانِيَ عِطْفِهِ (Turning his side away - 22:5) The word عِطْفِ ` itf means ` side of the body', and the expression means ` to turn on one's side' - in other words ` to oppose'.
Tazkirul Quran
Maulana Wahiduddin Khan
The Arabs had adopted polytheism in the erroneous belief that it was the Truth. When the Prophet’s call for belief in there being only the one God started shaking the faith of the idolators, those chiefs who had built their supremacy on the foundation of idolatory were perturbed, as they smelt danger. For the common man, the discarding of idolatory means only giving up the religion of his forefathers, while for a chief the destruction of idolatory amounts to the destruction of his supremacy. Therefore, in every age, the call for an uncorrupted faith is vehemently opposed by those who had built up and maintained their leadership on the strength of adulterated religion. Such people indulge in unnecessary arguments against the call to Truth and the giver of that call. They make all-out efforts to see that the people under their influence become suspicious of such a call, so that they will remain within the fold of their traditional religions as a matter of course. They thus oppose the Truth in order to maintain the false prestige and the supremacy which they had established on the basis of their self-made religion. They are more interested in themselves than in the Truth. Such people are the worst culprits in the eyes of God. On the Day of Judgement, nothing short of disgrace, humiliation and punishment will be their unmitigated fate.
Uthmani text of the Madinah mushaf (King Fahd Complex). Translation: Saheeh International. Tafsir via Quran.com.