Is it permissible for a man to occasionally invite a trustworthy Muslim friend (with or without his spouse) for a dinner while the host’s wife is present provided that the Islamic ethics in dress and speech are respected?
Yes, it would be permissible (rather recommended) to invite a fellow Muslim brother to one’s house for food even if the host’s wife is at home. There is nothing unlawful or detestable about this. Entertaining guests was the way of our beloved Messenger of Allah (Allah bless him & give him peace), his companions (Allah be pleased with them all) and the pious.
However, one must ensure that the injunctions of Shariah are not violated in terms of free mixing with the opposite gender. The host’s wife should not be alone at any time in a room (khalwa) with the male guest; neither should she mix freely and casually with him. Informal mixing with someone of the opposite gender is unlawful and must be avoided. Hence, the host’s wife should not sit and eat with her husband and his friend in a casual way, for that will be considered unlawful mixing with the opposite gender.
You may also read the article regarding mixed gatherings on this website.
And Allah knows best
[Mufti] Muhammad ibn Adam
Leicester , UK