Tafsir of Al-Balad 90:10

"And We have guided him to the two high ways."

Meaning, the two paths of good and evil, as narrated by al-Hakim—who authenticated it—al-Tabarani, and others, on the authority of Ibn Mas'ud. It was also narrated by 'Abd ibn Humayd and Ibn Jarir on the authority of Ibn Abbas, and it has been narrated from 'Ikrimah, al-Dahhak, and others. Al-Tabarani also narrated it from Abu Umamah in a marfu' (raised) form.

Al-Najd is well known as a raised path. Imru’ al-Qais said: "A group of them traversing the valley of Nakhla, And another of them crossing the highland (najd) of Kabkab."

Najd is named as such due to its elevation above the depression of Tihama. The favor spoken of here is that He (Glory be to Him) guided him and clarified to him (Exalted be His state) that whoever follows one [path] shall be saved, and whoever follows the other shall be destroyed. This favor is not contingent upon the actual traversal of the path of good. The Imam has equated this verse to His saying: "Indeed, We guided him to the way, whether he be grateful or ungrateful."

Describing the path of good with elevation and najdah (highness) is apparent, unlike the path of evil, for it contains a descent from the peak of natural disposition (fitra) to the abyss of wretchedness. Thus, the [term najdayn] is used by way of predominance (taghlib), or because the imagination perceives it [evil] as an ascent. For this reason, the concept of "ascent" (taraqqi) is used in reaching and perfecting every matter. This is what has been said.

Ibn Jarir and Ibn Abi Hatim narrated through various chains from Ibn Abbas that they are the two breasts. This has also been narrated from Ibn al-Musayyib, meaning the mother’s two breasts are like the two paths for the child’s life and sustenance; the elevation in them is apparent, and the belly below them is like the lowland. The Arabs swear by a mother’s two breasts, saying: "By her two high ones, I have not done it." This interpretation has also been attributed to Ali (may Allah ennoble his face). However, what is recorded in al-Durr al-Manthur—from the narration of al-Firyabi and 'Abd ibn Humayd, and likewise in Majma' al-Bayan—is that he (may Allah ennoble his face) was asked about people who say the two najdayn are the breasts, and he replied: "No, they are good and evil." Perhaps the one who held that [other] view saw that the wording allows for it, despite the favor being highly apparent in the former.