Deuteronomy 23 · a question people ask
The Moabite may not enter the LORD's assembly (23:3). Then how is Ruth the Moabitess in the line of David and of Jesus?
Here is what the verses say. The law: "An Ammonite or a Moabite shall not enter into the LORD’s assembly; even to the tenth generation shall no one belonging to them enter into the LORD’s assembly forever" (23:3). Ruth was one of "the women of Moab" (Ruth 1:4). She told Naomi, "Your people will be my people, and your God my God" (Ruth 1:16), and called herself "a foreigner" (Ruth 2:10), with the Hebrew word 23:20 uses for the foreigner. Boaz spoke "to the elders and to all the people" (Ruth 4:9) of "Ruth the Moabitess" (Ruth 4:10), and they answered, "We are witnesses" (Ruth 4:11). Her son Obed "is the father of Jesse, the father of David" (Ruth 4:17), and Matthew names her in Jesus' line: "Boaz became the father of Obed by Ruth" (Matthew 1:5). The book of Ruth never mentions Deuteronomy 23, and when Nehemiah's people read this law, "they separated all the mixed multitude from Israel" (Nehemiah 13:3). All agree on what the text shows: a woman of Moab took the LORD as her God and was received in Israel, and she stands in the line of David and of Jesus. Christians hold that together with 23:3 in two main ways.
How Christians read it
Where Christians differ, Favor sets out the main views side by side and doesn't pick one.
The law kept out Moab as a people
Those who read it this way note that the reasons given are what Ammon and Moab did as peoples: "they didn’t meet you with bread and with water" and "they hired against you Balaam" (23:4). Ruth left Moab and took the LORD as her God (Ruth 1:16), and Boaz blessed her as one who had come to the LORD, "under whose wings you have come to take refuge" (Ruth 2:12). They hold that the law kept out Moab, not one who had left Moab to join herself to the LORD, and they point to the LORD's word through Isaiah that a foreigner who has joined himself to the LORD should not say the LORD will separate him from his people (Isaiah 56:3).
Deuteronomy 23:4 · Ruth 1:16 · Ruth 2:12 · Isaiah 56:3
Mercy beyond what the law allowed
Those who read it this way take "forever" (23:3) as it stands, as Nehemiah's people did when they read it (Nehemiah 13:1-3). They hold that Ruth's place in Israel is the LORD's own doing, pointing to "the LORD enabled her to conceive" (Ruth 4:13) and to the women's words, "Blessed be the LORD, who has not left you today without a near kinsman" (Ruth 4:14), and they read her story as the LORD's mercy reaching one the law kept out.
Deuteronomy 23:3 · Nehemiah 13:1-3 · Ruth 4:13-14
The verses
“An Ammonite or a Moabite shall not enter into the LORD’s assembly; even to the tenth generation shall no one belonging to them enter into the LORD’s assembly forever,”
“They took for themselves wives of the women of Moab. The name of the one was Orpah, and the name of the other was Ruth. They lived there about ten years.”
“Ruth said, “Don’t urge me to leave you, and to return from following you, for where you go, I will go; and where you stay, I will stay. Your people will be my people, and your God my God.”
“Then she fell on her face and bowed herself to the ground, and said to him, “Why have I found favor in your sight, that you should take knowledge of me, since I am a foreigner?””