What is the ruling in Islamic law on a banquet that a person holds upon marriage and invites others to?

The wedding banquet is a Sunnah practice in principle. It falls under the Islamic recommendation of feeding others, provided that extravagance and waste are avoided, and that it does not involve unlawful food, drink, furnishings, or any form of prohibited entertainment. Furthermore, it should not be restricted to the rich while excluding the poor, and it should reflect excellence, proper conduct, and consideration of others.

Anas ibn Malik (may Allah be pleased with him) said,
“The Prophet (peace and blessings be upon him and his family) stayed between Khaybar and Madinah for three nights when he consummated his marriage to Ṣafiyah. I invited the Muslims to his wedding banquet, which had neither bread nor meat. Instead, he had Bilal lay out leather mats upon which he placed dates, dried yogurt, and ghee”
(recorded by Bukhari). Mulla ‘Ali al-Qari noted in Mirqat al-Mafatiḥ (5:2105), “This shows that the Prophet’s banquet did not contain the food of luxury and affluence, but rather the simple food of ascetic people, such as dates, dried yogurt, and ghee.”

 

Holding a wedding banquet

The wedding banquet is a Sunnah established by the Messenger of Allah (peace and blessings be upon him and his family) for it is reported that he practiced it. Safiyyah bint Shaybah (may Allah be pleased with her) said,
“The Prophet (peace and blessings be upon him and his family) held a banquet for one of his wives with two mudds of barley”
(reported by Bukhari).

Anas ibn Malik (may Allah be pleased with him) also reported that ‘Abd al-Raḥman ibn ‘Awf (may Allah be pleased with him) came to the Messenger of Allah (peace and blessings be upon him and his family) with traces of yellow perfume on him. The Prophet (peace and blessings be upon him) asked him about it, and he replied him that he had married a woman from the Ansar. The Prophet (peace and blessings be upon him) asked, “How much did you give her as dowry?” He replied, “The weight of a date pit in gold.” The Messenger of Allah (peace and blessings be upon him and his family) said, “Hold a banquet, even if with one sheep”
(recorded by Bukhari and Muslim). Imam Ibn Qudama noted in Al-Mughni (7:275), “There is no disagreement among the scholars that a wedding banquet is a prescribed Sunnah.”

And Allah Almighty knows best.