Sayyiduna Abu Huraira (may Allah be pleased with him) used to say that the worst food is the food of a wedding feast to which the rich are invited and the poor are left out, and whoever does not accept the invitation (without a valid Shari' excuse) has disobeyed Allah and His Messenger.

And with the same chain of narration (from Sayyiduna Abdullah bin Umar, may Allah be pleased with them), it is narrated that the Messenger of Allah, peace and blessings be upon him, said: "When any of you is invited to a wedding feast, he should accept it."