Answered by Shaykh Faraz Rabbani
Can a Muslim resturant allow customers to bring their own wine and provide glasses to serve the win in? Can the employees serve it?
Walaikum assalam wa rahmatullah,
I pray that this finds you well, and in the best of health and spirits. May Allah grant you all good and success in this life and the next.
One cannot announce that one allows customers to bring alcohol, nor serve it to them if they bring it.
The basis for this is the stern Qur’anic prohibition against alcohol, and the command to completely avoid it. The Messenger of Allah (peace and blessings be upon him) explained that among those who are cursed by Allah [i.e. completely distanced from His Mercy, and under His Anger] are the those who accept it and those who serve it. [Tirmidhi and Ibn Maja]
And Allah alone gives success.
Wassalam,