Is it permissible to rent an apartment to two Christian women, with whom there is a Christian man who is not related to them?

It is not permissible to rent property to someone of whom it
is known from his circumstances, or it is thought most likely, that he will
use the place to commit sin or help others in doing so. That is because
Allah, may He be exalted, says (interpretation of the meaning):

“And cooperate in righteousness
and piety, but do not cooperate in sin and aggression”

[al-Maa’idah 5:2].

If he does that, the rental contract is invalid, and the
landlord cannot keep the rent; rather he must give it in charity, because it
is unlawful wealth that is not permissible for him.

Shaykh al-Islam Ibn Taymiyah (may Allah have mercy on him)
said: It is not right to sell to one who intends to do haraam with (the
purchased items), such as juice which will be used to make wine, if he knows
that is the case, as is the view of Ahmad and others, or if he thinks that
this is likely, which is one of the two views. This is supported by the view
of his companions, who said: If the landlord thinks that the renter is
renting the house for sinful purposes, such as selling alcohol and the like,
it is not permissible for him to rent that house out to him, and the rent
contract is not valid. Selling and renting are the same. End quote from
al-Fataawa al-Kubra (5/388). 

If he rented the apartment to them as a residence, and he did
not know that they wanted it for sinful purposes, then there is no sin on
him, and the rent is lawful for him, but after that, if he finds out that
they are committing sin in the apartment, he should tell them not to do
that, and when the rental period expires, he should not renew the rental
contract with them.

As-Sarkhasi (may Allah have mercy on him) said: There is
nothing wrong with a Muslim renting a property to a dhimmi for the latter to
live in, then if he drinks alcohol there, or worships the cross, or bring
pork into it, there is no sin on the Muslim for any of that, because he did
not rent it out for that purpose; the sin is the action of the tenant, and
his action was not intended by the landlord, so there is no sin on the
landlord in that case. End quote.

Al-Mabsoot
(16/39).

The scholars of the Standing Committee for Issuing Fatwas
were asked:

Is it permissible to rent houses to the people of the Book
and to evildoers among the Muslims? Because some of the scholars regard that
as haraam, based on the fact that the kitaabi will disbelieve in Allah in
this house, and he will worship the cross there, and eat pork and drink
alcohol; and based on the fact that the evildoer will drink alcohol there,
and he will listen to music.

They replied:

The basic principle is that it is permissible to rent houses
to people of the Book who have a covenant with the Muslims and are under
Muslim protection, but if the landlord knows or thinks it most likely that
this place will be used for things that Allah has forbidden, such as selling
alcohol, gambling and the like, then it is haraam [to rent the place to
them], because that comes under the heading of helping or cooperating in sin
and transgression, whether the tenant is a disbeliever or a sinner, and
whether what is rented to him is a house, or a shop, or anything else. That
is because Allah, may He be exalted, says (interpretation of the meaning):

“And cooperate in righteousness
and piety, but do not cooperate in sin and aggression”

[al-Maa’idah 5:2].

End quote.

Fataawa al-Lajnah ad-Daa’imah
(14/487-486].

Shaykh Ibn ‘Uthaymeen (may Allah have mercy on him) said:

If someone rents a house from you, intending to put a stage
in it for idle entertainment, then renting it to him is haraam. But if he
rents it from you to live in it, then he puts a stage in it for idle
entertainment, then renting it to him is not haraam. The difference is that
in the first case, he rented it for the purpose of committing an unlawful
action, and in the second case he rented it for a permissible purpose, but
then he committed an unlawful action in it. End quote.

Sharh al-Kaafi
(4/15).

Based on that, in the first scenario, in which the rent is
haraam, it is not permissible for the landlord to keep it or benefit from
it, or to use it for ‘umrah; rather he must give it in charity.

In the second scenario, in which the rent is halaal, there is
nothing wrong with him using it for ‘umrah.

And Allah knows best.