Abbas - Tanwîr al-Miqbâs min Tafsîr Ibn ‘Abbâs
(Say) O Muhammad to the people of Mecca: (Who guardeth you) who protects you (in the night or in the day from the Beneficent) from the chastisement of the Beneficent? It is also said that this means: who protects you from the punishment of other than the Beneficent? (Nay, but they turn away from) but they disbelieve and discard the (the mention of their Lord) from the profession of Allah's divine Oneness and the Scripture of their Lord,
Say, to them: ‘Who can guard you, preserve you, by night and day from the Compassionate One?’, from His chastisement, if it should befall you? In other words, no one can do such a thing. Those being addressed [here] do not fear God’s chastisement because they deny [the truth of] it. Nay, but of the Remembrance of their Lord, that is, the Qur’ān, they are disregardful, failing to reflect on it.
(Indeed (many) Messengers were mocked before you, but the scoffers were surrounded by what they used to mock.) meaning, the punishment which they thought would never come to pass. This is like the Ayah:
(Verily, Messengers were denied before you, but with patience they bore the denial, and they were hurt; till Our help reached them, and none can alter the Words of Allah. Surely, there has reached you the information (news) about the Messengers (before you)) 6:34. Then Allah menitons His favor for His creatures; He protects them by night and by day, taking care of them and watching over them with His Eye that never sleeps.
(Say: "Who can guard and protect you in the night or in the day from the Most Gracious'') means, other than the Most Gracious Himself
بَلْ هُمْ عَن ذِكْرِ رَبِّهِمْ مُّعْرِضُونَ
(Nay, but they turn away from the remembrance of their Lord.) means, they do not recognize the blessings and favor of Allah towards them; they turn away from His signs and blessings.
أَمْ لَهُمْ آلِهَةٌ تَمْنَعُهُمْ مِّن دُونِنَا
(Or have they gods who can guard them from Us) This is a rhetorical question aimed at denouncing and rebuking. The meaning is, do they have any gods who can protect them and take care of them other than Us It is not as they imagine or as they claim. Allah says:
لاَ يَسْتَطِيعُونَ نَصْرَ أَنْفُسِهِمْ
(They have no power to help themselves,) these gods on whom they rely instead of Allah cannot even help themselves.
وَلاَ هُمْ مِّنَّا يُصْحَبُونَ
(nor can they be protected from Us.) Al-`Awfi reported from Ibn `Abbas,"Nor can they be guarded from Us.''
Maududi - Sayyid Abul Ala Maududi - Tafhim al-Qur'an
That is to say, "Who is there to protect and save you from the scourge of Allah if you are suddenly visited by it any time during the night or day?"
In other words it means: "These people have been deluded by Our favor and Our provisions. They think they are enjoying prosperity and good life as their personal right and there is none to take it away from them. They have forgotten that there is God above them Who is able to make or mar their fortune".
In this connection, see Ar-Ra`d (XIII): 41 and E. N. 60 thereof. Here it bears an additional meaning also: "Do they not see that an All-Powerful Being is showing His Signs every now and then everywhere on the earth in the form of famines, epidemics, floods, earthquakes and other calamities; millions of people are killed, habitations and harvests are destroyed and other damages are caused, which frustrate all human designs?"
It means: "When they know that all the resources and provisions of life are in Our hands and that We can increase or decrease them as We will, have they the power and strength to defend themselves against Our punishment? Can they not see from these "Signs" that their power, prosperity and luxury are not everlasting and that there is an All-Powerful Allah to seize and punish them?"
That is, "The same scourge which they are demanding to be hastened and of which they are making fun."