Overall meaning : Allah, Exalted be He, states that never did He send any of His prophets to a town and its people disbelieved him but He seized them with poverty and diseases so that they would humble themselves and beseech Him to remove their distress. When such trial was of no avail and they persisted in transgressing Allah’s limits, He changed their bad condition into a good one by restoring their heath and providing them with abundance until they increased in number, their wealth and offspring multiplied and said, 'Our forefathers had also seen both adversity and prosperity.’ Then Allah’s punishment seized them suddenly when they least expected it.
The Almighty then explains that had the people of those towns believed and feared Him by doing what He commands and avoiding what He forbids, He would have showered upon them blessings from heaven and earth, but instead they disbelieved, and so He inflicted punishment on them for their unbelief and the sins they had committed. Do the unbelieving people of the towns, then, feel secure from Allah’s severe punishment coming upon them at night while they are asleep?! Or do they feel secure form the coming of punishment upon them in the early part of the day while they are at play, sunk in utter heedlessness?! Do they feel secure from Allah’s indulging them in His blessings despite their sins, as He did with those before them, thereby leading them step by step to their ruin?! Only the losers who are doomed to ruin feel secure against Allah’s indulging them in His blessings despite their unbelief and persistence in sin and then seizes them unawares.
Has it, then, not become clear to those who have inherited the earth after the destruction of its former residents that, if Allah so willed, He could also destroy them as well for their sins and seal their hearts, leaving them bereft of hearing the truth and accepting it?!