The Literal Commandment
When the LORD your God brings you into the land where you are entering to possess it, and clears away many nations before you, the Hittites and the Girgashites and the Amorites and the Canaanites and the Perizzites and the Hivites and the Jebusites, seven nations greater and stronger than you, and when the LORD your God delivers them before you and you defeat them, then you shall utterly destroy them. You shall make no covenant with them and show no favor to them. Furthermore, you shall not intermarry with them; you shall not give your daughters to their sons, nor shall you take their daughters for your sons. (Deuteronomy 7:1-3)
The literal commandment is that we should not intermarry with the seven nations that were in the Land.
Messiah Says
Messiah implicitly affirmed this commandment when He spoke about the Law:
"Do not think that I came to abolish the Law or the Prophets; I did not come to abolish but to fulfill. For truly I say to you, until heaven and earth pass away, not the smallest letter or stroke shall pass from the Law until all is accomplished. Whoever then annuls one of the least of these commandments, and teaches others to do the same, shall be called least in the kingdom of heaven; but whoever keeps and teaches them, he shall be called great in the kingdom of heaven. (Matthew 5:17-19)
Paul exhorts those in Corinth that they should not be "bound together with unbelievers; for what partnership have righteousness and lawlessness, for what fellowship has light with darkness?" (2 Corinthians 6:14)
Pictures of Messiah
When a man marries a woman, she becomes his bride. In Israel, a man was forbidden from marrying a woman who was not part of the covenant.
In a similar fashion, when we are called to faith, we become part of the bride of Messiah. We cannot become part of the bride unless we are first part of the new covenant.
How Messiah Fulfilled
Messiah never fulfilled this commandment because He never physically married a woman.
Traditional Observance
The traditional observance of this commandment is that a Jew should not marry anyone who is not a Jew. Jews are permitted to marry converts.
There is precedent in Scripture for such conversion in the story of Ruth (who was from Moab). She declares to Naomi, "where you go, I will go, and where you lodge, I will lodge. Your people shall be my people, and your God, my God." This can be seen as a declaration of her intent to convert to Judaism and become a member of the covenant.
Other Notes
We are able to fulfill this commandment today and we should not marry those who are not part of the covenant.
What about someone who comes to faith who is already married? That is a much more complex issue that we will not attempt to solve here.
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