You asked

what current economic systems might embody a 'brother' or 'foreigner' distinction?

Adds the setting and its conversation across both testaments.

Deuteronomy 23:19-20

“You shall not lend on interest to your brother: interest of money, interest of food, interest of anything that is lent on interest. To a foreigner you may lend on interest; but to your brother you shall not lend on interest, that Yahweh your God may bless you in all that you put your hand to, in the land into which you are entering to possess it.”

This passage is part of a larger collection of laws in the book of Deuteronomy, presented as Moses' farewell speeches to the Israelites on the plains of Moab before they enter the promised land. These laws outline how the community should live justly and maintain its distinct identity under God's covenant.

What responsibilities do we hold towards those within our immediate communities compared to those outside them, especially in economic dealings?

Then — the setting

This law emerged in ancient Israel, likely around the 7th-6th centuries BCE, though attributed to Moses prior to Israel's entry into Canaan. The distinction between 'brother' (fellow Israelite) and 'foreigner' was crucial in a society primarily agricultural and tribal, where mutual support within the kinship group was vital for survival, especially during times of hardship or poor harvest. Charging interest to a 'brother' was seen as exploitative, potentially driving them into irreversible poverty or debt-slavery, thus undermining the social fabric and covenant ideal of a community free from economic oppression. Foreigners, on the other hand, were often merchants engaging in commercial loans, and the same social protections were not extended to them.

Across the Testaments

The Old Testament, particularly the Torah, consistently prohibits charging interest to fellow Israelites (e.g., Exodus 22:25, Leviticus 25:35-37). This reflects a covenantal concern for internal social justice and the protection of the vulnerable within God's people. The New Testament, while not directly repealing this specific law, broadens the concept of 'neighbor' and 'brother' significantly. Jesus' teachings (e.g., the Parable of the Good Samaritan, Luke 10:25-37) extend the ethic of compassion and care to all people, regardless of ethnic or national origin. Luke 6:34-35 even encourages lending to those from whom no return is expected, pushing beyond the Deuteronomic permission to charge interest to foreigners, toward a universal ethic of selfless generosity.

Keep thinking

Read alongside it

Leviticus 25:35-37
This passage also prohibits charging interest to fellow Israelites, emphasizing support for the poor within the community.
Psalm 15:5
It lists not lending money at interest to the righteous as a characteristic of one who dwells with God.
Luke 6:34-35
Jesus encourages lending even to sinners without expecting repayment, challenging the Deuteronomic distinction to a universal ethic of generosity.

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