Muslims living in non-muslim countries or in Muslim countries where there is a reasonable non-muslim population usually face a problem that whether it is allowed for them to marry a non-muslim girl such as Christians?
Sheikh Saalih received a similar question from a man who wanted to marry a Christian girl. Sheikh responded that Islam allows a Muslim man to marry chaste Christian woman based on the verse of the Quran:
(Lawful to you in marriage) are chaste women from the believers and chaste women from those who were given the Scripture (Jews and Christians) [al-Maa’idah 5:5]
But the question is whether the Christians today are even proper Christians? And are they chaste? If yes then you can marry them if not then you are not allowed to marry them.
But sheikh said we don’t recommend you to marry a Christian woman, even we don’t recommend you to marry just a Muslim girl rather spouse should be chosen on the bases of the commitment to religion.
Prophet (peace and blessings of Allaah be upon him) said: “A woman may be married for four reasons: her wealth, her lineage, her beauty and her religious commitment. Choose the one who is religious, may your hands be rubbed with dust [i.e., may you prosper].” (Bukhaari, 4802)