What is the ruling on the wife and her father refusing to complete the marriage because a wedding celebration was not held?

It is not permissible for the wife and her family to burden the husband beyond his capacity, nor to spend money on forbidden things such as mixed musical parties. He is not obliged to obey them in this, for Allah Almighty says: "And cooperate not in sin and aggression" [Al-Ma'idah 5:2]. And He says: "It is not for a believing man or a believing woman, when Allah and His Messenger have decided a matter, that they should [thereafter] have any choice about their affair" [Al-Ahzab 33:36]. Customs are to be respected unless they contradict the Sharia.

It is recommended for the husband to hold a wedding feast (walimah) according to his capacity, for Allah Almighty says: "Allah does not burden a soul beyond its scope" [Al-Baqarah 2:286]. And the Prophet, peace be upon him, said to Abdur-Rahman ibn Awf: "Hold a feast, even with one sheep." Extravagance and squandering are forbidden, for Allah Almighty says: "And do not be extravagant. Indeed, He does not like extravagants" [Al-An'am 6:141]. And "Indeed, the squanderers are brothers of the devils" [Al-Isra 17:27]. A wedding feast is recommended, not obligatory.

It is appropriate to accommodate the wife and her family in customs that do not contradict the Sharia, while showing them respect, and seeking the help of people of knowledge and virtue to reconcile between them and clarify the truth for them, for Allah Almighty says: "And if you fear dissension between the two, send an arbitrator from his people and an arbitrator from her people. If they both desire reconciliation, Allah will cause agreement between them" [An-Nisa 4:35].