18.54
Abbas - Tanwîr al-Miqbâs min Tafsîr Ibn ‘Abbâs
(And verily We have displayed) We have explained (for mankind) for the people of Mecca (in this Qur'an all manner of similitudes) all forms of threats and promises in order that they take heed and, hence, believe, (but man) Ubayy Ibn Khalaf al-Jumahi (is more than anything contentious) in respect to falsehood; it is also said that this means: no one is more contentious than man.
And verily We have dispensed We have explained for mankind in this Qur’ān an example of every kind of similitude min kulli mathalin is an adjective qualifying an omitted clause in other words ‘We have dispensed therein a similitude from every kind of similitude that they may be admonished. But man is most disputatious he is most contentious in matters of falsehood jadalan is a specification derived from al-insān ‘man’ the subject of kāna in other words the meaning is that the disputatiousness of man is what can be found in him most.
Allah says, `In this Qur'an, We have explained to mankind and given clear details of matters so that they will not stray from the truth or be misled from the path of guidance. Despite this explanation, man is very quarrelsome and opposes truth with falsehood,' except for those whom Allah guides to the path of salvation. Imam Ahmad recorded that `Ali bin Abi Talib said that the Messenger of Allah came to visit him and Fatimah, the daughter of Allah's Messenger at night, and said,
«أَلَا تُصَلِّيَانِ؟»
(Are you not going to pray) I said, "O Messenger of Allah, our souls are in the Hand of Allah. If He wills to wake us, He will wake us.'' When I said that, he went away without returning. Then I heard him as he was walking away, slapping his thigh and saying,
وَكَانَ الإِنْسَـنُ أَكْثَرَ شَىءٍ جَدَلاً
(But, man is ever more quarrelsome than anything.)'' It was also recorded in the Two Sahihs.
18.54-55
Maududi - Sayyid Abul Ala Maududi - Tafhim al-Qur'an
This is to warn the people that the Qur'an has left no stone unturned in making the Truth plain. It has employed all kinds of arguments, parables, similitudes and used all the possible effective ways to appeal to the heart and the mind of man, and adopted the best possible style. In short, nothing has been left that could persuade the people to accept the Truth. If, in spite of this, they do not accept the truth, it is obvious that they are waiting for God's scourge like the one that visited the former communities to make them realize their error.