Tafsir of Al-Muddathir 74:26

(سأصليه سقر) is a substitution for (سأرهقه) as a substitution of inclusion (badal al-ishtimal), because Saqar includes hardships and a mountain of fire. The description that follows does not contradict the substitution, based on the intent of a "mountain," premised on the fact that what is meant by it is similar to what is mentioned in the Hadith.

Abu Hayyan stated: "It appears they are two separate sentences, each following the other as a way of threatening the disobedience that preceded each one. Thus, he threatened him for being obstinate toward the verses of Allah the Exalted with 'imposing an arduous punishment' (sa'ud), and for his statement that the Quran is 'magic being narrated' with 'cast him into Saqar'." There is an investigation regarding this which is not hidden to those who have encompassed the information that has preceded.