Musnad Shihab

Explanation:
The scholars have presented several interpretations of this hadith, but in our view, the preferred opinion is that this hadith should not be taken literally, because all human beings—whether righteous or wicked, Muslim or disbeliever—are created in the same way. It is not the case that one person has one intestine and another has seven. If we conduct experiments and perform surgery, we will see that just as a believer has one intestine, so too does a disbeliever have only one. Therefore, this hadith is not to be understood according to its apparent meaning, but rather as a metaphor and simile, and that is regarding “worldly desire.” The meaning is that the disbeliever is solely inclined toward the world; his concern and striving are only to fill his belly, whereas Allah, the Exalted, has granted the believer contentment (qana‘ah). He takes from the world only as much as is necessary for his subsistence, and all his remaining concern and effort are for religion and the Hereafter.

‘Allamah Tahawi said: I heard Ibn Abi ‘Imran say that a group interprets this hadith as referring to desire for the world, just as it is said that so-and-so is “devouring the world,” meaning he is inclined toward the world and is greedy for it. The believer eats with one intestine because he is disinterested in the world, and the disbeliever eats with seven intestines because he is desirous of the world. This group did not interpret the hadith as referring to food (eating); they say that we have seen many believers eat more than disbelievers, and if this hadith were interpreted as referring to food, then its meaning would be problematic (difficult). [شرح مشكل الآثار : 5/ 258]