فَعَصَوا رَسولَ رَبِّهِم فَأَخَذَهُم أَخذَةً رابِيَةً
Then they disobeyed the apostle of their Lord, so He seized them with a terrible seizing.
EXEGESIS
Most exegetes explain the terrible seizing as an intense and painful punishment, unprecedented even as a chastisement.
The word rābiyah (terrible) denotes that which surpasses all others and also that which is incremental. It comes from the word ribwah, the same root from which ribā (usury) and yarbū (increase) (30:39) are derived. In the case of ʿĀd, the chastisement increased in its intensity and pain over seven gruelling nights and eight days (verse 7), whilst for others, like the people of Prophet Noah (a), the increment transitioned on to the next world almost immediately: they were drowned then [immediately] made to enter a fire (71:25), meaning they suffered a devastating punishment in this world that increased in the next. The same was the case for the Pharaoh and his clan who, after drowning in this world, suffer more torment in the intermediate world that only increments further on Judgement Day: The fire to which they are exposed morning and evening. And on the day when the hour sets in Pharaoh’s clan will enter the severest punishment (40:46).
Since this verse continues from the previous and, they disobeyed refers to all those peoples mentioned earlier, the apostle of their Lord is a general reference to the individual apostle(s) sent to each one of them. So, for Pharaoh and his people, the apostle of their Lord is Prophet Moses (a) and Prophet Aaron (a); for the nations that were before him (verse 9) the apostle would be Prophet Noah (a), Prophet Shuʿayb (a), and so on; and for the towns that were overturned (verse 9), the apostle of their Lord would be Prophet Lot (a). It is similar to 50:12-14 where several rebellious nations are listed and thereafter it concludes, each impugned the apostles (50:14), meaning each one of them denied their individual apostle, or that in denying their own apostle, in essence they denied all the apostles.
EXPOSITION
In one sense, all the apostles are like one body because their message is the same; and that is why Prophet Moses (a) and Prophet Aaron (a) are told: So approach Pharaoh and say: ‘We are indeed an apostle (rasūl) of the Lord of the worlds’ (26:16) – note the singular – and in another sense, each one of them represents all of the apostles because denying one is like denying all of them, and that is why The people of Noah impugned the apostles (26:105), [The people of] ʿĀd impugned the apostles (26:123), [The people of] Thamūd impugned the apostles (26:141), The people of Lot impugned the apostles (26:160), and so on, when in fact, each one of them belied only the one apostle that was sent to them.
No nation was destroyed unjustly (11:117) until an apostle was first sent to guide and warn them against disobeying God (17:15). And conversely, every nation to which an apostle was sent was also tried with hardships and tests (7:94).
So He seized them with a terrible seizing by punishing each nation uniquely: some with earthquakes, thunderclaps, and hurricanes, others with drowning, and yet others with raining down rocks on them and turning their towns upside down. And yet all were punished through natural causes, just like His blessings, that come to man through natural means – including His prophets who are, at face-value, ordinary humans (25:7, 25:20, 64:6) sent from their own communities (10:74, 14:4).
More importantly, however (and as explained in the Exposition of verse 5), these divine chastisements were, in reality, nothing but a manifestation of the evil of the community on whom they befell and seized: So the evils of what they had earned visited them, and they were besieged (ḥāqa bihim) by what they used to deride (16:34).
[1] Qurtubi, 18/262; Razi, 3/623.