Tafsir of Al-Kahf 18:103

{Their efforts have gone astray} They are lost and void. They are the monks, according to Ali (may Allah be pleased with him), similar to His saying: {Laboring, weary} (Al-Ghashiyah: 3).

Mujahid said: They are the People of the Book.

Ali (may Allah be pleased with him) also narrated that Ibn al-Kawwa asked him about them, and he replied: "Among them are the people of Harura."

Abu Sa'id al-Khudri said: "People will come on the Day of Resurrection with deeds that they consider as great as the mountains of Tihama, but when they are weighed, they will weigh nothing."

{So We will not assign any weight to them on the Day of Resurrection} We will hold them in contempt, and they will have no weight or status with Us.

It is also said: No scale will be set up for them, because the scale is only placed for the people of good and evil among the monotheists. It is also recited as la yuqimu (He will not set up) with a ya.

If you ask: In what grammatical position is "those whose efforts have gone astray"? I say: The most likely position is nominative (raf'), as in: "They are those whose efforts have gone astray," because it is an answer to the question. It is also permissible for it to be in the accusative (nasb) as a form of dispraise, or in the genitive (jarr) as an appositive (badal).

{Hell} An explanatory appositive ('atf bayan) for His saying: {their recompense}.

{Indeed, those who have believed and done righteous deeds will have the Gardens of Paradise as a lodging * abiding therein, not desiring any change from it}