Tafsir of Al-Fajr 89:19

"And you consume the inheritance (al-turath)": that is, the legacy. Its root is wirth, and the waw has been substituted with a ta’, as in tukhmah (indigestion) and tuk’ah (a reclining cushion) and similar instances.

"With a greedy consuming (aklan lamman)": meaning [you consume] with intense greed (lam), or it is the lam itself used for emphasis. Al-lam is gathering; from this is the saying of al-Nabighah: "And I am not one to keep a brother whom I gather (tulummuhu) despite his shortcomings." That is, gathering together. What is intended here is gathering between the lawful and the unlawful, and between that which is praiseworthy and that which is blameworthy. From this is the saying of al-Hutay’ah: "If he is one who gathers (lamman) seeking the blame of his Lord, may the Merciful not sanctify those grinders (teeth)."

This means that in your consuming, you combine your own share of the inheritance with the shares of others. It is narrated that they would not allow women or young children to inherit; they would consume their shares, saying, "None shall take the inheritance except those who fight and protect the territory." This was despite them knowing from the law of Ishmael, peace be upon him, that they [women and children] do inherit. Thus, the argument that "the Surah is Meccan while the verses of inheritance are Medinan" is refuted, for the knowledge of what is lawful and what is unlawful is not known except through the Sharia, as the rational [theories] of good and evil are not a position held by us.

It is also said that it means: you consume what the deceased heir left behind—having been gathered from both lawful and unlawful sources—knowing that to be the case, and thus you gather in your consuming between his lawful and his unlawful [wealth].

In al-Kashshaf, it is permitted that it [the verse] criticizes the heir who attained the wealth easily and effortlessly, without breaking a sweat, and so he becomes extravagant in spending it and consumes it with a vast consumption, gathering together various types of desired foods, drinks, fruits, and the like, as idle heirs do. This [interpretation] is critiqued as being unsuitable for the [surrounding] context.