Ibn Majah

Benefits and Issues:
➊ By "eating with seven intestines" is meant eating excessively.
➋ Greed and avarice are not befitting of a believer's character.
➌ Eating to the point of fullness is harmful to health; therefore, one should eat only as much as can be easily digested.
➍ A believer eats by mentioning the name of Allah, and thus there is blessing in his food. A disbeliever does not mention the name of Allah when eating, so there is no blessing in his food, and Satan becomes a partner with him in his eating.

Hadith Commentary:
The content of the hadith is in the sense of "mostly" (as a general rule), not that only those who eat excessively are disbelievers. Some Muslims also eat excessively, but eating less is better.

Hadith Commentary:
The meaning of this hadith is:
All of the disbeliever’s desire is to fill his belly, thus he eats like animals do, whereas the true objective of the believer is the attainment of the Hereafter. Therefore, he suffices with eating little, only enough to maintain the connection between body and soul. Eating little is an excellent characteristic of faith, while greed for excessive eating is a characteristic of disbelief.
In any case, a believer should eat to satisfy his hunger and be content with eating a small amount.

Hadith Commentary:
In the explanation of this hadith, Shah Waliullah Muhaddith Dehlawi rahimahullah states that its meaning is that all of the disbeliever’s greed is centered on his stomach, whereas the true objective of the believer is the Hereafter.
Thus, the characteristic of a believer is precisely this: eating little is among the finest qualities of faith, and the greed for excessive eating is a trait of disbelief.
(Hujjat Allah al-Baligha)

Hadith Commentary:
(1)
Allamah Qurtubi rahimahullah has written that the "seven intestines" refers to seven characteristics that are found in the disbeliever. They are: natural desire, desire of the self (nafs), desire of the eye, desire of the mouth, desire of the ear, desire of the nose, and the desire of hunger. This last one (the desire of hunger) is necessary, in which the believer eats, while the disbeliever eats in all of them. (Umdat al-Qari: 405/14)

(2)
Hafiz Ibn Hajar rahimahullah has written that, regarding eating, people are of three categories:
➊ Those who devour every kind of food, whether they need it or not. Such behavior is that of ignorant people.
➋ A group who eat when hungry and eat only enough to remove their hunger.
➌ Some people remain hungry to break the desire of the self (nafs), and eat only enough to maintain the connection between body and soul.
Most likely, the second category is what is meant by the hadith, because this is the characteristic of the believer, while the first category is that of the disbelievers. (Fath al-Bari: 699/9)

Hadith Commentary: Benefits and Issues: This type of incident has occurred with several disbelievers who became Muslim: Abu Ghazwan, Jahjah Ghifari, Abu Basrah Ghifari, Nadhla bin Amr, and Thumamah bin Uthal. Qadi Iyad and Imam Nawawi have identified Nadhla bin Amr as the subject of this hadith, but Hafiz Ibn Hajar is not satisfied with this identification (Fath al-Bari, Chapter: The Believer Eats With One [Person], Vol. 9).

Hadith Authentication:
[وأخرجه البخاري 5396، من حديث مالك به]

Jurisprudential Explanation:
➊ Generally, one should eat little, but sometimes, according to necessity, eating to one's fill is also permissible. See: Al-Muwatta Hadith: 119
➋ Extravagance and unnecessary expenses in eating and drinking are not good deeds; rather, one should strive to adopt frugality. However, at times of necessity—such as hosting guests and friends, or in accordance with a legitimate desire—preparing and presenting the best food and eating it oneself is also correct, just as our master Ibrahim (alayhis salam) slaughtered a calf for his guests, roasted its meat, and presented it to them.
➌ It is necessary to avoid anything that is harmful; for example, a diabetic must abstain from sugar.
➍ By eating less, with the grace and mercy of Allah, health remains good.
➎ The disbeliever eats and drinks excessively. See: Al-Muwatta Hadith: 445
➏ It is narrated from our master Miqdam bin Ma'dikarib (radi Allahu anhu) that I heard the Messenger of Allah (sallallahu alayhi wa sallam) say: "No vessel that the son of Adam fills is worse than his stomach. It is sufficient for the son of Adam to eat a few morsels to keep his back straight. If eating is necessary, then one third should be for food, one third for drink, and one third for breathing." [سنن الترمذي : 2380 وقال : ”هٰذا حديث حسن صحيح“ أحمد 4/132 ح17318، دوسرا نسخه : 17186، وسنده حسن]
➐ Another excellent point in this hadith is that the world is not merely for eating, drinking, and resting; rather, this world is the abode of action. For the people of faith, the pleasure of Allah is primary, and eating and drinking are of secondary importance.

Hadith Authentication (Takhrij al-Hadith):
[وأخرجه مسلم 2063، من حديث ما لك به ، و من رواية يحي بن يحي . وجاء فى الأصل : ”يستمتها“]

Jurisprudential Explanation (Tafaqquh):
➊ Islam commands good conduct even towards disbelievers.
➋ For the purpose of inviting to Islam, it is commendable for Muslims of correct creed to establish relations with disbelievers and innovators.
➌ The objective of disbelievers is worldly life, eating and drinking, and plundering and attacking Muslims.
➍ It is permissible to accept an invitation from a disbeliever, provided that some Shariah-compliant or permissible benefit is attained thereby.
➎ Also see: [الموطأ حديث: 367، البخاري 5396]