Surah Saba · سُوْرَةُ سَبَاٍ · Juz 22
Q 34:14
فَلَمَّا قَضَيْنَا عَلَيْهِ ٱلْمَوْتَ مَا دَلَّهُمْ عَلَىٰ مَوْتِهِۦٓ إِلَّا دَآبَّةُ ٱلْأَرْضِ تَأْكُلُ مِنسَأَتَهُۥ ۖ فَلَمَّا خَرَّ تَبَيَّنَتِ ٱلْجِنُّ أَن لَّوْ كَانُوا۟ يَعْلَمُونَ ٱلْغَيْبَ مَا لَبِثُوا۟ فِى ٱلْعَذَابِ ٱلْمُهِينِ
Translations
And when We decreed for Solomon death, nothing indicated to the jinn his death except a creature of the earth eating his staff. But when he fell, it became clear to the jinn that if they had known the unseen, they would not have remained in humiliating punishment.Puis, quand Nous décidâmes sa mort, il n'y eut pour les avertir de sa mort que la «bête de terre», qui rongea sa canne. Puis lorsqu'il s'écroula, il apparut de toute évidence aux djinns que s'ils savaient vraiment l'inconnu, ils ne seraient pas restés dans le supplice humiliant [de la servitude].Tafsir
When we decreed for Solomon to die, the Jinn did not realise he had passed away until the woodworms had eroded away the staff he was leaning on. When he fell it became clear to the Jinn that they do not know the unseen/ghayb, as if they did, they would have not remained subdued, continuing to carry out the difficult tasks imposed upon them.
Read Ibn Kathir (Ibn Kathir (abridged, English))
Then when We decreed death for him, nothing informed them (Jinn) of his death except a little worm of the earth which kept (slowly) gnawing away at his stick. So when he fell down, the Jinn saw clearly that if they had known the Unseen, they would not have stayed in the humiliating torment (14)
The Death of Sulayman
Allah tells us how Sulayman, peace be upon him, died and how Allah concealed his death from the Jinn who were subjugated to him to do hard labor. He remained leaning on his stick, which was his staff, as Ibn 'Abbas may Allah be pleased with him, Mujahid, Al-Hasan, Qatadah and others said. He stayed like that for a long time, nearly a year. When a creature of the earth, which was a kind of worm, ate through the stick, it became weak and fell to the ground. Then it became apparent that he had died a long time before. It also became clear to Jinn and men alike that the Jinn do not know the Unseen as they (the Jinn) used to imagine and tried to deceive people. This is what Allah says:
مَا دَلَّهُمْ عَلَىٰ مَوْتِهِ إِلَّا دَابَّةُ الْأَرْضِ تَأْكُلُ مِنْسَأَتَهُ ۖ فَلَمَّا خَرَّ تَبَيَّنَتِ الْجِنُّ أَنْ لَوْ كَانُوا يَعْلَمُونَ الْغَيْبَ مَا لَبِثُوا فِي الْعَذَابِ الْمُهِينِ
(nothing informed them (Jinn) of his death except a little worm of the earth which kept (slowly) gnawing away at his stick. So when he fell down, the Jinn saw clearly that if they had known the Unseen, they would not have stayed in the humiliating torment.) meaning, it became clear to the people that they (the Jinn) were lying.
Arabic text: Tanzil (Uthmani). Translations: Sahih International (en), Muhammad Hamidullah (fr). tanzil.net