The consumption of small amounts of food guarantees tenderness of the heart, strength of the intellect, humility of the self, weakness of desires, and gentleness of temperament. Immoderate eating brings about the opposite of these praiseworthy qualities.
Al-Miqdam ibn Ma’d Yakrib said that he heard the Messenger of Allah, sallallahu ‘alayhi wa sallam, say:
“The son of Adam fills no vessel more displeasing to Allah than his stomach. A few morsels should be enough for him to preserve his strength. If he must fill it, then he should allow a third for his food, a third for his drink and leave a third empty for easy breathing.”
[Sahih, Ahmad, al-Musnad, 4/132; as-Sa’ati, al-Fath ar-Rabbani, 17/88; at-Tirmidhi, Kitab az-Zuhud, 7/51]
Excessive eating induces many kinds of harm. It makes the body incline towards disobedience to Allah and makes worship and obedience seem laborious-such evils are bad enough in themselves. A full stomach and excessive eating have caused many a wrong action and inhibited much worship. Whoever safeguards against the evils of overfilling his stomach has prevented great evil. It is easier for Shaytan to control a person who has filled his stomach with food and drink, which is why it has often been said:
“Restrict the pathways of Shaytan by fasting.”
[Da’if; it does not appear in most of the sources of the sunnah, but is mentioned in al-Ghazali’s al-Ihya, 8/1488]
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