Tafsir of Surah Al-Kahf 18:50
﴿وَإِذْ قُلْنَا لِلْمَلَائِكَةِ اسْجُدُوا لِآدَمَ فَسَجَدُوا إِلَّا إِبْلِيسَ كَانَ مِنَ الْجِنِّ فَفَسَقَ عَنْ أَمْرِ رَبِّهِ أَفَتَتَّخِذُونَهُ وَذُرِّيَّتَهُ أَوْلِيَاءَ مِن دُونِي وَهُمْ لَكُمْ عَدُوٌّ بِئْسَ لِلظَّالِمِينَ بَدَلًا﴾
Translation of the meaning
And [mention] when We said to the angels, "Prostrate to Adam," and they prostrated, except for Iblees. He was of the jinn and departed from [i.e., disobeyed] the command of his Lord. Then will you take him and his descendants as allies other than Me while they are enemies to you? Wretched it is for the wrongdoers as an exchange.
English Translation - Noor International Center — v1.1.2 · QuranEnc.comThe words of the two imams are given in their original Arabic, verbatim, with references.
Shaykh al-Islam Ibn Taymiyyah
والإبدال من الشيء يقتضي ترك المبدل منه؛ إذ لا يجمع بين البدل والمبدل منه«اقتضاء الصراط المستقيم لمخالفة أصحاب الجحيم» 1/486