In this vein...
In this vein, a tradition is narrated on the authority of Abu Sa’id Khudri to the effect that Muslims contemporaneous with the Noble Prophet of Islam (S) could never imagine that disputations might occur between Muslims holding that they share the same Creator and religion.
It was on the Day of Siffin that two apparently Muslim parties waged war against each other that Abu Sa’id learned that the Verse concerns them as well.[^1] Nonetheless, the following Verses demonstrate that the disputation occurred between the Noble Prophet (S) and believers on the one hand and the polytheists and liars on the other.
It is well known in the history of Islam that following the sad demise of the Noble Prophet of Islam (S), ‘Umar denied his death saying that the Prophet (S) might not die but he had gone to his Lord in the same manner that Moses had been in occultation away from his people for forty days but had returned to them. Likewise, the Messenger of God (S) would return and the hands and feet of those believing in his death was to be severed!
Then, who does more wrong than one who utters a lie against Allah, and denies the truth when it [i.e., the truth] comes to him? Is there not in Hell an abode for disbelievers? The word “truth” (sidq) in the blessed Verse indicates Divine Word Revealed to the Prophet (S) as the Holy Qur’an. The preceding Verses treated of people on the Day of Judgment and disputations occurring then.
The Verse in question resumes the same discussion dividing people into “the lying” and “the trustworthy.” The former have two characteristics as reflected in the Qur’anic Verse in question: “Then, who does more wrong than one who utters a lie against Allah, and denies the truth when it [i.e., the truth] comes to him?” Polytheists and disbelievers uttered many a lie concerning God; for instance, some regarded angels His daughters, some others regarded Jesus (as) his son, some considered idols as intercessors interceding on their behalf, and some others forged false injunctions as to lawfulness and unlawfulness.