ما الدليل من السنة على عدم أكل الناذر من نذره؟

If the one making a vow intends a specific recipient for their vow, such as the poor or relatives, then the vow must be spent on them, due to the Prophet's (peace be upon him) saying: "Deeds are only by intentions."

If they did not have an intention for a specific recipient, is it permissible for them to eat from the vow? There is a difference of opinion among scholars regarding this: - The Malikis and some Shafi'is permitted eating from an absolute vow that was not designated for the needy. - The majority of scholars prohibited eating from the vow, because it is a charity, or because it is like the compensation for hunting or the compensatory blood sacrifices in Hajj, or because the one making the vow has relinquished what they vowed from their possession to Allah.

The opinion that it is not permissible to eat from the vow is more sound, more cautious, and more exculpatory, unless the one making the vow stipulated or intended to eat from it.