One of the reasons for the weakening of the modern church is that many Christians have married unbelievers. Such a practice is a sign of unfaithfulness towards God and leads to serious negative consequences, particularly apostasy.
Who one chooses as a spouse is important. And the most important thing in considering a spouse is whom that person worships. How can a marriage succeed if it is not built on Christ?
The Bible makes this clear throughout. While preachers occasionally cite the two New Testament passages on intermarriage (1 Corinthians 7:39; 2 Corinthians 6:14), they rarely mention the Old Testament references. This is an error on the part of the church, as there is actually a biblical theology of marrying unbelievers (or “intermarriage” as the OT often calls it).
The Patriarchs and Marriage in Genesis
God’s prohibition on marrying unbelievers begins in the Pentateuch, though it is not explicit until the Mosaic period. God instituted marriage in Genesis 2:24, a “one flesh” covenant between a man and a woman. However, this foundational text says nothing about whom a person should marry.
Some argue that the practice of intermarriage between believers and unbelievers began in Genesis 6:1-4 (between the godly line of Seth and the ungodly line of Cain), but I argue elsewhere that this actually refers to intermarriage between angels and humans. Thus this is a different kind of intermarriage altogether, though also prohibited!
When it comes to the patriarchs in Genesis, their focus was on marrying within the family and avoiding marriage with the neighboring Canaanites. It was understood that when families marry sons and daughters to one another, they become “one people” (Genesis 34:4). Thus Abraham sent Isaac to his brother Nahor to find a wife (Genesis 24:2-4), and Rebekah sent Jacob to her brother Laban to find a wife (Genesis 27:42-45). The Jacob story emphasizes this point, as Jacob’s brother Esau married two Hittite women (also called “Canaanites”) that displeased Isaac and caused Rebekah to “loathe” her life (Genesis 26:34-35; 27:46; 28:6-9). Isaac therefore explicitly instructed Jacob to not take a Canaanite wife but marry one of Laban’s daughters (Genesis 28:1-5).
The text never says that these relatives of Isaac and Jacob worshiped Yahweh, but Rebekah and Rachel (and Leah) at least came to worship Yahweh. Abraham and Rebekah must have known that their family members were converted at some point or that the women would submit to the worship of Yahweh. (It is unclear how many worshipers of Yahweh were alive at the time, but it was probably few.) Either way, the Book of Genesis is clear that the patriarchs wanted to avoid intermarriage with the Canaanites, a theme expanded upon throughout the Pentateuch and the rest of the Old Testament.
The Prohibition of Intermarriage in the Pentateuch
The primary passages prohibiting intermarriage with unbelievers (particularly Canaanites) are found in Exodus and Deuteronomy. Yahweh gave these commands to the people of Israel prior to the conquest of the land of Canaan, as He knew that intermarriage with the Canaanites would be a temptation for Israel. Both these passages emphasize that marrying sons and daughters off to Canaanites would result in Israelite sons and daughters worshiping (or “whoring after”) the gods of the Canaanites:
Observe what I command you this day. Behold, I will drive out before you the Amorites, the Canaanites, the Hittites, the Perizzites, the Hivites, and the Jebusites. Take care, lest you make a covenant with the inhabitants of the land to which you go, lest it become a snare in your midst. You shall tear down their altars and break their pillars and cut down their Asherim (for you shall worship no other god, for the LORD, whose name is Jealous, is a jealous God), lest you make a covenant with the inhabitants of the land, and when they whore after their gods and sacrifice to their gods and you are invited, you eat of his sacrifice, and you take of their daughters for your sons, and their daughters whore after their gods and make your sons whore after their gods (Exodus 34:11-16)
When the LORD your God brings you into the land that you are entering to take possession of it, and clears away many nations before you, the Hittites, the Girgashites, the Amorites, the Canaanites, the Perizzites, the Hivites, and the Jebusites, seven nations more numerous and mightier than you, and when the LORD your God gives them over to you, and you defeat them, then you must devote them to complete destruction. You shall make no covenant with them and show no mercy to them. You shall not intermarry with them, giving your daughters to their sons or taking their daughters for your sons, for they would turn away your sons from following me, to serve other gods. Then the anger of the LORD would be kindled against you, and he would destroy you quickly. But thus shall you deal with them: you shall break down their altars and dash in pieces their pillars and chop down their Asherim and burn their carved images with fire. For you are a people holy to the LORD your God. The LORD your God has chosen you to be a people for his treasured possession, out of all the peoples who are on the face of the earth (Deuteronomy 7:1-6).
God instructed the Israelites to drive out the Canaanites so that Israel would inherit the land that God promised to Abraham. God is quite clear that Israel was to make no covenant with the Canaanites—which included the covenant of marriage. The key takeaway here is that God knew intermarriage with unbelievers would lead His people into worship of other gods and ultimately apostasy.
Intermarriage and Idolatry in the Prophets
Israel conquered the land of Canaan in the Book of Joshua, but they failed to complete the conquest and let some Canaanites remain in the land. Therefore in his charge near the end of his life, Joshua restated Yahweh’s prohibition on marrying the Canaanites:
Be very careful, therefore, to love the LORD your God. For if you turn back and cling to the remnant of these nations remaining among you and make marriages with them, so that you associate with them and they with you, know for certain that the LORD your God will no longer drive out these nations before you, but they shall be a snare and a trap for you, a whip on your sides and thorns in your eyes, until you perish from off this good ground that the LORD your God has given you (Joshua 23:11-13).
There were two commands that God made very clear for the Israelites: (1) Drive out the Canaanites completely; and (2) Do not intermarry with the Canaanites. Joshua warned that disobedience to these commands would result in the Canaanites becoming a “snare” and a “thorn” to Israel (Joshua 23:13; cf. Exodus 23:33; Num 33:55; Deuteronomy 7:16; Judges 2:3). And that is exactly what took place in the Book of Judges.
Judges shows what happened to Israel as a result of disobedience towards Yahweh. Israel transgressed Yahweh’s covenant by worshipping false gods, so Yahweh left the Canaanites in the land as a “test” for Israel (Judges 2:20–3:5). Unsurprisingly, the Israelites intermarried with the peoples of Canaan:
And their daughters they took for themselves for wives, and their own daughters they gave to their sons, and they served their gods (Judges 3:6).
So Israel not only failed to drive out the Canaanites, but they then intermarried with them. This is why God made such an important point about driving these peoples out (Exodus 34:16; Deuteronomy 7:3-4; Joshua 23:12). By leaving the people in the land, Israel became like the Canaanites. Intermarriage in particular led the Israelites to abandon Yahweh and worship the Baals and Ashtaroth (Judges 2:13).
However, this practice of marrying unbelievers saw its low point about 400 years after the time of the judges, under the monarchy of King Solomon (971–931 B.C.). The Book of Judges made a point about Israel not having a king—“In those days there was no king in Israel. Everyone did what was right in his own eyes” (Judges 21:25). Well here Israel had a king, and he took intermarriage with unbelievers to a new level:
Now King Solomon loved many foreign women, along with the daughter of Pharaoh: Moabite, Ammonite, Edomite, Sidonian, and Hittite women, from the nations concerning which the LORD had said to the people of Israel, “You shall not enter into marriage with them, neither shall they with you, for surely they will turn away your heart after their gods.” Solomon clung to these in love. He had 700 wives, who were princesses, and 300 concubines. And his wives turned away his heart. For when Solomon was old his wives turned away his heart after other gods, and his heart was not wholly true to the LORD his God, as was the heart of David his father. For Solomon went after Ashtoreth the goddess of the Sidonians, and after Milcom the abomination of the Ammonites. So Solomon did what was evil in the sight of the LORD and did not wholly follow the LORD, as David his father had done. Then Solomon built a high place for Chemosh the abomination of Moab, and for Molech the abomination of the Ammonites, on the mountain east of Jerusalem. And so he did for all his foreign wives, who made offerings and sacrificed to their gods (1 Kings 11:1-8).
Solomon is the paradigmatic bad king, as he broke the laws concerning kings in Deuteronomy 17:14-20. Specific to marriage, Solomon violated Deuteronomy 17:17—“And he shall not acquire many wives for himself, lest his heart turn away.” Solomon acquired 1,000 wives, 300 of whom were concubines (essentially second-class wives).
But Solomon not only took many wives, he also married “foreign” women—thus violating God’s more general prohibition in Exodus 34:16 and Deuteronomy 7:3-4. In fact, 1 Kings 11:2 loosely cites Deuteronomy 7:3-4 when it says that Solomon married women “from the nations concerning which the LORD had said to the people of Israel, ‘You shall not enter into marriage with them, neither shall they with you, for surely they will turn away your heart after their gods.’”
Of course, Solomon’s wives turned his heart away from Yahweh to other gods. He worshiped the gods of other nations and even offered sacrifices to them. Solomon’s idolatry led to Yahweh tearing the kingdom into two (1 Kings 11:11-13). The northern Kingdom of Israel and the southern Kingdom of Judah declined over the years, until Israel was destroyed by the Assyrians in 722 B.C. and Judah was taken into captivity in 586 B.C.
Intermarriage and Idolatry in the Writings
However, God preserved Judah and restored them to the land of Canaan in 539 B.C. They returned in three waves, the second of which was led by Ezra in 458 B.C. However, God’s people had fallen into sin again, this time explicitly intermarrying with the Canaanites:
After these things had been done, the officials approached me [Ezra] and said, “The people of Israel and the priests and the Levites have not separated themselves from the peoples of the lands with their abominations, from the Canaanites, the Hittites, the Perizzites, the Jebusites, the Ammonites, the Moabites, the Egyptians, and the Amorites. For they have taken some of their daughters to be wives for themselves and for their sons, so that the holy race has mixed itself with the peoples of the lands. And in this faithlessness the hand of the officials and chief men has been foremost.” As soon as I heard this, I tore my garment and my cloak and pulled hair from my head and beard and sat appalled (Ezra 9:1-3).
This again was a violation of Exodus 34:16 and Deuteronomy 7:3-4. The Canaanites still lived in the land because Israel failed to drive them out completely, and here they are still a thorn in Israel’s side almost 1,000 years after the initial conquest. (The Egyptians, Ammonites, and Moabites were now in the land along with the groups considered “Canaanites”—Canaanites, Hittites, Perizzites, Gergashites, Amorites, and Jebusites.) God’s people intermarried with them, and now the “holy race has mixed with the peoples of the lands.” Like King Solomon, this intermarriage in Ezra 9 was led by Israel’s leaders—“officials and chief men” (Ezra 9:2).
This sin against Yahweh led Ezra to confess before God and seek mercy (Ezra 9:6-15). Ezra even appeals to God’s prohibition of intermarriage in his prayer:
For we have forsaken your commandments . . . ‘do not give your daughters to their sons, neither take their daughters for your sons, and never seek their peace or prosperity, that you may be strong and eat the good of the land and leave it for an inheritance to your children forever’ (Ezra 9:10-12).
Ezra’s prayer here cites multiple commandments, including Deuteronomy 7:3 and Deuteronomy 23:6. The latter reference makes sense because it is in the context of the Ammonites and Moabites (Deuteronomy 23:3-6), two of the people groups the Israelites had intermarried with in addition to the Canaanites (Ezra 9:1). Deuteronomy 7:3 only explicitly forbade intermarriage with the Canaanites.
Ezra’s leadership led the people of Israel to make a covenant with God to “put away all these wives and their children,” and Ezra commanded the people to separate from their foreign wives (Ezra 10:3, 11). The passage includes a list of Israelites who had married foreign women (Ezra 10:18-44).
We may wonder how God’s people could divorce their wives and put away their children, as this seems to violate the important principle of loyalty to one’s marriage covenant. However, there are two reasons why this was a unique situation and is not normative for today.
First, Israel had violated God’s specific prohibition of marrying Canaanites in order to prevent idolatry and apostasy (Exodus 34:16; Deuteronomy 7:3-4). Thus Ezra’s concern of the remnant’s intermarriage was focused on the “impurity” of the peoples and their “abominations” (Ezra 9:11, 14).
Second, Ezra was dealing with a remnant of Israel, and intermarriage threatened the nation’s very survival (Ezra 9:8, 15). The remnant could not last if they immediately apostatized through intermarriage. Therefore, this was a special circumstance in Israel and does not encourage the practice of divorce, even if a person is married to an unbeliever (see below).
The Apostle Paul’s Prohibition of Marrying Non-Christians
This Old Testament history forms the background of the Apostle Paul’s prohibition against Christians marrying non-Christians. The most explicit New Testament teaching comes in 1 Corinthians 7, where Paul addresses issues of marriage and divorce. Christians who are married to unbelievers are not to separate or divorce an unbelieving spouse, though it cannot always be prevented when an unbelieving spouse divorces a Christian (1 Corinthians 7:12-16).
However, the Apostle Paul gives an important command regarding marriage in his instructions regarding widows:
A wife is bound to her husband as long as he lives. But if her husband dies, she is free to be married to whom she wishes, only in the Lord (1 Corinthians 7:39).
A Christian should stay faithful to his or her spouse while both are alive. However, if a spouse dies, a Christian is free to remarry. Only Paul adds an important caveat—“only in the Lord.” Christians are only to marry Christians. Why? This is best explained by looking at the more commonly cited passage of 2 Corinthians 6:14, where Paul commands Christians not to be “unequally yoked with unbelievers.”
If Christ has saved us from our sins, if He is our Lord, and if we worship Him above all things—then how can we marry someone who does not share this? Marriage is the most important relationship in life, and whom one worships is the most important thing about a person. Thus Paul says:
Do not be unequally yoked with unbelievers. For what partnership has righteousness with lawlessness? Or what fellowship has light with darkness? What accord has Christ with Belial? Or what portion does a believer share with an unbeliever? What agreement has the temple of God with idols? For we are the temple of the living God; as God said,
“I will make my dwelling among them and walk among them,
and I will be their God,
and they shall be my people.
Therefore go out from their midst,
and be separate from them, says the Lord,
and touch no unclean thing;
then I will welcome you,
and I will be a father to you,
and you shall be sons and daughters to me,
says the Lord Almighty” (2 Corinthians 6:14-18).
God explicitly forbade His people in the Old Testament from marrying Canaanites because they worshiped false gods, a practice that Yahweh knew would lead Israel astray. And just as God foretold, Israel’s intermarriage led to apostasy exemplified during the period of the judges and Solomon’s reign (though prevented after the return of the exiles from captivity). The prohibition was based on religion and not ethnicity, as God’s people were free to marry non-Israelites who converted to the worship of Yahweh (e.g. Rahab was a Canaanite; Ruth was a Moabite.)
The New Testament builds on this background. As worshipers of Christ, we should not marry people who do not worship Christ. Unbelievers worship false gods, and intermarriage with unbelievers will lead Christians into apostasy. May pastors be faithful in preaching against intermarriage with unbelievers, and may Christians be faithful in marrying only in the Lord. In this way, the church will be a faithful bride of Christ (Ephesians 5:22-24; Revelation 19:7). For it is only through godly marriage practices that we can remain faithful to Christ and raise godly children who will do the same.
 The land of Canaan was inhabited by seven groups of people at the time of the conquest in the Book of Joshua. Joshua 3:10 lists the Canaanites, Hittites, Hivites, Perizzites, Girgashites, Amorites, and Jebusites. The Table of Nations in Genesis 10 lists the Hittites (sons of Heth), Hivites, Gergashites, Amorites, and Jebusites as sons of the man named “Canaan” (Ham’s son), leaving out only the Perizzites. Thus all the inhabitants of the land of Canaan are often called “Canaanites.” However, the two most prominent groups in the area at the time of Joshua were the Amorites in the east (“beyond the Jordan to the west”) and the Canaanites in the west (“by the sea”) (Joshua 5:1).
 Ezra’s references in Ezra 9:10-12 to Deuteronomy 7:3 and Deuteronomy 23:6 cover all the people groups listed in Ezra 9:1 except for the Egyptians. However, Ezra is possibly appealing to Deuteronomy 4:20-24 and thus referencing the Egyptians when he uses language about “good of the land” and “inheritance to your children forever” in Ezra 9:12. Similar language is used in Deuteronomy 4:20-24, where Moses spoke of Yahweh bringing Israel “out of the iron furnace, out of Egypt, to be a people of his own inheritance, as you are this day” (Deuteronomy 4:20). Moses spoke of “good land” that Yahweh was giving as an “inheritance” (Deuteronomy 4:21), and he warned Israel not to make a “carved image” (Deuteronomy 4:23; cf. 4:15-19), which is probably a contrast with the ways of the Egyptians. Thus Ezra may have referenced this passage because it connected Egyptians with idolatry.