Before Dhū al-Qarnayn acts, God names the source of his capacity: اِنَّا مَكَّنَّا لَهُ فِي الْاَرْضِ وَاٰتَيْنَاهُ مِنْ كُلِّ شَيْءٍ سَبَبًاۙ. God established him in the earth and gave him the means needed for the tasks of his rule. His power and resources are gifts from God. Then the next ayah is almost bare: فَاَتْبَعَ سَبَبًا. He followed a route. Divine enabling does not produce passivity; human exertion does not erase the Giver. Yūsuf too was established in the earth by God, first when he was received into an Egyptian household and later when he held authority, and that establishment was joined to mercy and the preservation of the reward of those who do excellent work. Dhū al-Qarnayn’s journeys begin under the same order: capacity is granted, responsibility follows.

God places a choice before him: اِمَّٓا اَنْ تُعَذِّبَ وَاِمَّٓا اَنْ تَتَّخِذَ ف۪يهِمْ حُسْنًا, either punish or treat them well. Dhū al-Qarnayn chooses to call them to faith, then distinguishes their responses. اَمَّا مَنْ ظَلَمَ: whoever persists in the wrong of associating others with God will face the ruler’s punishment, then be returned to his Lord for a terrible punishment in the Hereafter. Earthly authority neither replaces nor exhausts divine judgment. But وَاَمَّا مَنْ اٰمَنَ وَعَمِلَ صَالِحًا, whoever believes and does righteous deeds, will have the finest reward from God. Dhū al-Qarnayn adds, وَسَنَقُولُ لَهُ مِنْ اَمْرِنَا يُسْرًاۜ: what we require of him will be easy. The ruler’s treatment follows the distinction God has made, and his favor toward the believer follows God’s greater promise. Establishment in the earth becomes a charge to serve faith and righteousness, as elsewhere it is joined to prayer, giving, and the command of what is right.

They offer Dhū al-Qarnayn payment: فَهَلْ نَجْعَلُ لَكَ خَرْجًا, shall we pay you to place a barrier between us and them? His answer repeats the truth with which the narrator introduced him: مَا مَكَّنّ۪ي ف۪يهِ رَبّ۪ي خَيْرٌ. What my Lord has established me in is better. The wealth and resources already granted to him suffice; he does not need their payment. He asks instead, فَاَع۪ينُون۪ي بِقُوَّةٍ: assist me with strength. Their labor and materials become part of their protection. Elsewhere the Qur’an asks whether the Messenger seeks payment and answers that the provision of his Lord is better. In both passages, the sufficiency of God’s gift frees its recipient to serve without demanding the people’s wealth.

The difference between Dhū al-Qarnayn and the owner of the two gardens can be heard in their first-person speech. The garden owner said, “I am greater than you in wealth and stronger in followers.” Dhū al-Qarnayn says, “What my Lord has established me in is better.” One boasts that he has more than his companion; the other names his Lord as the Giver. The garden owner’s supporters fail him when his property collapses. Dhū al-Qarnayn uses his strength to organize the strength of vulnerable people. One imagines possession as protection; the other turns granted capacity into protection for others.

The construction is narrated through material commands: اٰتُون۪ي زُبَرَ الْحَد۪يدِۜ, bring me blocks of iron; انْفُخُواۜ, blow; then اٰتُون۪ٓي اُفْرِغْ عَلَيْهِ قِطْرًاۜ, bring me molten copper to pour over it. He fills the space between the mountainsides, heats the iron until it glows like fire, and pours the copper over it. Mercy takes form through craft, planning, heat, labor, and command. Elsewhere Dāwūd is taught to make coats of mail, Sulaymān receives flowing copper, and the household of Dāwūd is commanded to work in gratitude. Iron itself is described alongside the Book and the balance as containing great force and benefits for people. Al-Kahf shows that force becoming benefit through protection of the vulnerable.

The result is materially successful: فَمَا اسْطَاعُٓوا اَنْ يَظْهَرُوهُ وَمَا اسْتَطَاعُوا لَهُ نَقْبًا. They can neither surmount it nor pierce it. Only after its effectiveness has been established does Dhū al-Qarnayn interpret it: هٰذَا رَحْمَةٌ مِنْ رَبّ۪يۚ. This is mercy from my Lord. He immediately announces its end: فَاِذَا جَٓاءَ وَعْدُ رَبّ۪ي جَعَلَهُ دَكَّٓاءَۚ. When the promise of my Lord comes, He will make it level. The garden owner had looked at a flourishing work and said, مَٓا اَظُنُّ اَنْ تَب۪يدَ هٰذِه۪ٓ اَبَدًاۙ, I do not think this will ever perish. Dhū al-Qarnayn looks at an impenetrable work and confesses that God will destroy it. A work need not last forever to fulfill a righteous purpose. Dhū al-Qarnayn protects the people, acknowledges the source of his power, and accepts the end God appoints.

Al-Kahf has now shown mercy taking material form in three structures. The cave shelters young believers until God raises and discloses them. The repaired wall preserves an orphan inheritance until the boys reach maturity. The barrier protects a vulnerable people until the Lord’s promise comes. Each protection answers a need within time. Its limited task does not make it useless; its usefulness does not make it ultimate. The command that no refuge can be found apart from God remains over cave, wall, and rampart alike. God gives protection through these places; none can provide refuge from Him.

Dhū al-Qarnayn closes his account of the barrier with وَكَانَ وَعْدُ رَبّ۪ي حَقًّاۜ: the promise of my Lord is true. Earlier, the sleepers were discovered so that people might know that God’s promise is true and that there is no doubt concerning the Hour. The two narratives meet in that confession. The cave shows that even centuries of deathlike absence cannot prevent God from raising. The barrier shows that even the strongest human construction cannot prevent the promised end. God awakens those who seemed beyond return and will level what seems beyond breach. Time, matter, and human expectation remain beneath His true promise.

The narrative does not end as a report of successful engineering. The barrier’s levelling opens directly into the end: surging multitudes, the Trumpet, universal gathering, and displayed Hell. Al-Anbiyāʾ gives the only other Qur’anic naming of Yaʾjūj and Maʾjūj, describing their release and their streaming from every elevation just as the true promise draws near.

Human beings had earlier been presented before their Lord in ranks. Now Hell is presented before the disbelievers: وَعَرَضْنَا جَهَنَّمَ يَوْمَئِذٍ لِلْكَافِر۪ينَ عَرْضًاۙ. They are those اَلَّذ۪ينَ كَانَتْ اَعْيُنُهُمْ ف۪ي غِطَٓاءٍ عَنْ ذِكْر۪ي, whose eyes were covered from the signs that should have led them to remember and magnify God, وَكَانُوا لَا يَسْتَط۪يعُونَ سَمْعًا۟, and who could not hear. Their aversion to the truth is pictured as an utter incapacity to listen. The account began by offering a remembrance concerning Dhū al-Qarnayn; it ends before people who would not attend to God’s signs. What they refused to heed through revelation is now unavoidable before their eyes.

The sūrah has already condemned taking Iblīs and his descendants as protectors apart from God. Now it asks, اَفَحَسِبَ الَّذ۪ينَ كَفَرُٓوا اَنْ يَتَّخِذُوا عِبَاد۪ي مِنْ دُون۪ٓي اَوْلِيَٓاءَۜ: did the disbelievers suppose that they could take My servants as protectors apart from Me? Even honored servants, such as angels and prophets, cannot become gods to worship or patrons who save their worshippers from God’s judgment. The Book descended upon a servant. Mūsā found a servant given mercy and knowledge. Neither gift permits the servant to become a rival to God. No human given Book, judgment, or prophethood may call people to become servants to him apart from God or to take prophets and angels as lords. The honor bestowed on God’s servants calls for fidelity to what they teach, not worship of those who teach it.

The warning now turns from false protectors to wasted effort: قُلْ هَلْ نُنَبِّئُكُمْ بِالْاَخْسَر۪ينَ اَعْمَالًاۜ. Shall We tell you who are the greatest losers in their deeds? ضَلَّ سَعْيُهُمْ فِي الْحَيٰوةِ الدُّنْيَا: their striving in worldly life has come to nothing, وَهُمْ يَحْسَبُونَ اَنَّهُمْ يُحْسِنُونَ صُنْعًا, while they suppose that they are doing excellent work. The next ayah identifies them: they rejected their Lord’s signs and the meeting with Him. They may have labored hard and been convinced of their own excellence, yet their rejection has deprived their work of its hoped-for reward. Elsewhere the Qur’an describes people who receive the worldly fruit of their efforts but find their works void in the Hereafter. Visible results and confidence in one’s own goodness cannot establish acceptance before God.

The verdict falls on their works: فَحَبِطَتْ اَعْمَالُهُمْ—their works have become void. فَلَا نُق۪يمُ لَهُمْ يَوْمَ الْقِيٰمَةِ وَزْنًا: We will hold them of no account on the Day of Resurrection. Earlier, the record left no small or great deed uncounted. Now the sūrah distinguishes a recorded deed from an accepted one: their works confer no standing or honor before God. This is no failure of His justice; the Qur’an elsewhere promises that even a mustard-seed’s weight is brought and no soul is wronged. Their recompense also completes an earlier charge. They had taken God’s signs and warning as mockery; now the verdict names their unbelief and their mockery of His signs and messengers.

Hell is prepared for the disbelievers نُزُلًا; the gardens of الْفِرْدَوْسِ are promised to those who believe and do righteous deeds نُزُلًا. The same word names two opposed forms of hospitality: a terrible reception for the rejecters and a generous welcome for the believers. Earlier, Fire and gardens had been called an evil and a beautiful resting place. Now the contrast reaches its final form. Those admitted to these gardens remain there, لَا يَبْغُونَ عَنْهَا حِوَلًا, desiring no move elsewhere. Their abiding joy does not become weariness. The owner of the earthly garden had falsely assigned permanence to his estate; here permanence belongs to the hospitality God prepares after judgment. Al-Muʾminūn describes its inheritors through humble prayer, avoidance of idle speech, giving, chastity, and care for trusts and covenants. Faith and righteous action end in a home they never wish to leave.

The sūrah’s disclosures do not exhaust the Lord’s knowledge. قُلْ لَوْ كَانَ الْبَحْرُ مِدَادًا لِكَلِمَاتِ رَبّ۪ي لَنَفِدَ الْبَحْرُ قَبْلَ اَنْ تَنْفَدَ كَلِمَاتُ رَبّ۪ي وَلَوْ جِئْنَا بِمِثْلِه۪ مَدَدًا. If the sea were ink for the words of my Lord, the sea would be exhausted before the words of my Lord were exhausted, even if another like it were brought as replenishment. The opening declared the Book free of crookedness; none can alter the Lord’s words; now those words prove inexhaustible. Luqmān multiplies the image further—every tree as pen and seven seas as supply—yet the words of God still do not end.

The final قُلْ turns from the inexhaustibility of God’s words to the exact status of the one who recites them: اِنَّمَٓا اَنَا۬ بَشَرٌ مِثْلُكُمْ يُوحٰٓى اِلَيَّ. I am only a human like you, to whom revelation is given. The Messenger’s humanity does not diminish revelation; revelation does not erase his humanity. What is revealed is the sūrah’s final theological center: اَنَّمَٓا اِلٰهُكُمْ اِلٰهٌ وَاحِدٌۚ. Your God is only one God. Fuṣṣilat repeats the same confession and immediately commands turning steadfastly toward the one God and seeking His forgiveness. The servant’s distinction lies in receiving and transmitting revelation, not in becoming a second object of worship.

Then the whole sūrah is compressed into one demand: فَمَنْ كَانَ يَرْجُوا لِقَٓاءَ رَبِّه۪ فَلْيَعْمَلْ عَمَلًا صَالِحًا وَلَا يُشْرِكْ بِعِبَادَةِ رَبِّه۪ٓ اَحَدًا. Whoever hopes to meet his Lord must do righteous deeds and associate no one in the worship of his Lord. Hope seeks a gracious reception, and it leads into action now. The greatest losers had worked while rejecting the meeting; the believer works in hope of it. But the work must also be devoted to God: the prohibition reaches both worship of another deity and worship performed to win other people’s praise. The sūrah’s opening test—who is best in deeds—thus reaches its final demand: righteous action with worship reserved for the one Lord. Al-ʿAnkabūt likewise answers the hope of meeting God with the certainty of His appointed term. The appointed meeting gives urgency to the action required now.