When choosing a marriage partner, compatible religious outlook is one of the main factors to consider. As a general rule, it is preferable for Muslims to marry other Muslims. The Qur'an emphasizes this: “Do not marry unbelieving women until they believe; a slave woman who believes is better than an unbelieving woman, even if you are attracted to her” (Qur'an 2:221). At the time of this verse's revelation, marrying a slave was considered a great humiliation. However, Islam establishes that a person's faith is more important than social status or any other factor.

Under no circumstances is a Muslim, man or woman, allowed to marry a polytheist. However, under certain circumstances Muslim men are permitted to marry Jewish or Christian women: “Lawful for you in marriage are not only chaste women who are believers, but chaste women from among the people of the book revealed before your time, when you give them their due dowers” (Qur'an 5:5). Regardless of the faith of one's spouse, Muslims are still held to the standard of kindness, tenderness, and mutual respect in the marriage relationship.

Muslim women may marry only Muslim men, according to the following verse: “They are not lawful wives for the unbelievers, nor are the unbelievers lawful husbands for them” (Qur'an 60:11). Muslims perceive this rule as a protection for the woman in marriage. If a Muslim woman were to marry outside the faith, her husband would neither understand nor follow Islamic teachings about fair treatment of women or her rights and responsibilities. Such a marriage would put her at risk of abuse or the pressure to give up her faith.