Narrated Nafi`:
Ibn `Umar never used to take his meal unless a poor man was called to eat with him. One day I brought a poor man to eat with him, the man ate too much, whereupon Ibn `Umar said, "O Nafi`! Don't let this man enter my house, for I heard the Prophet (ﷺ) saying, "A believer eats in one intestine (is satisfied with a little food), and a kafir (unbeliever) eats in seven intestines (eats much food).
Narrated Ibn `Umar:
Allah's Messenger (ﷺ) said, "A believer eats in one intestine (is satisfied with a little food), and a kafir (unbeliever) or a hypocrite eats in seven intestines (eats too much).
Narrated `Amr:
Abu Nahik was avaricious eater. Ibn `Umar said to him, "Allah's Messenger (ﷺ) said, "A Kafir (unbeliever) eats in seven intestines (eats much)." On that Abu Nahik said, "But I believe in Allah and His Apostle ."
Ibn 'Umar reported Allah's Messenger (ﷺ) as saying that a non-Muslim eats in seven intestines whereas a Muslim eats in one intestine.