The Prophet (ﷺ) said: He who does not accept an invitation which he receives has disobeyed Allah and His Apostle, and he who enters without invitation enters as a thief and goes out as a raider.

Abu Dawud said: Aban bin Tariq is unknown.
Sunan Abi Dawud Book 28, Hadith 6
← Previous Hadith when one of you is invited to a meal, he must accept. If he wishes he may eat, but if he wishes(to leave), he may leave.

Sunan Abi Dawud Book 28, Hadith 5 Next Hadith → The worst kind of food is that at a wedding feast to which the rich are invited and from which the poor are left out. If anyone does not attend the feast to which he was invited, he has disobeyed Allah and His Apostle (may peace upon him).

Sunan Abi Dawud Book 28, Hadith 7