Interfaith marriage in Christianity
An interfaith marriage is typically defined as a marriage between a Christian and a non-Christian. Within the sects of Christianity, this may be extended to include inter-denominational marriage.
Some Christian local churches and churches at large may forbid interfaith marriage, basing this ban on New Testament verse 2 Corinthians 6:14 and, in some cases, the Old Testament verse Deuteronomy 7:3 (see also Ezra 9–10.). Likewise, such marriages are indirectly supported by part of the Pauline privilege, in 1 Corinthians 7:12–14, with the central excerpt: "For the unbelieving husband is sanctified through his (believing) wife, and the unbelieving wife is sanctified through her believing husband." However, it is to be noted that the context of 2 Corinthians 6:14 is not directly concerned with the question of marriage itself. Further, Deuteronomy 7:3 was with respect to Jewish law.
The New Testament does not otherwise broach the topic. Over time, this has effectively left the matter to be specified by the various denominations themselves or be based on local customs or attitudes of the day. Of the Christian denominations, the Roman Catholic Church has the best-defined set of criteria on interfaith marriage recognition. The Eastern Orthodox have rules which are in most respects similar to the Catholics.
The Roman Catholic Church requires permission for mixed marriages, which it terms all unions between Catholics and baptized non-Catholics (Eastern Orthodox and many Protestants). Such marriages are valid, though illicit, without this specific permission. The pastor of the Catholic party has authority to grant such permission. Also, historically, the mixed marriage cannot be officiated by a non-Catholic pastor as doing so would warrant excommunication for the Catholic partner. The baptized non-Catholic partner does not have to convert. Previously, the baptized non-Catholic partner had to agree to raise the children Catholic, but under current rules only the Catholic spouse must promise to do so.
The Roman Catholic Church has often discouraged marriages with Muslims and Jews, due to the fact that it is sometimes difficult to raise children in the faith after a marriage, especially if the woman is Catholic.
Marriages between a Catholic and an unbaptized person are not sacramental and fall under the impediment of disparity of worship (Code of Canon Law, Cn.1086 § 1).  They are invalid without a dispensation, for which authority lies with the bishop ordinary of the place of marriage (Cn. 1086 § 2). In addition, the Catholic Church recognizes the Pauline privilege, wherein a Catholic may marry an unbaptized previously married person who consents to convert, but only if the unbaptized person's spouse refuses to become a Catholic also (similar to Muslim views on marrying previously-married non-Muslims).
- Max D. Younce, Is there any Scriptural advice concerning Protestants marrying Catholics?
- Are inter-faith marriages prohibited by the Bible?
- "Avoid marrying Muslims advises Portuguese cardinal". 15 Jan 2009.