Interest

There's also a full written article on Interest in the Reference Library.

Income from loaning money, usually called usury in the scriptures, but not generally signifying unlawful or unjust rates

Deuteronomy 23:19 Deuteronomy 23:20 Ezekiel 18:8 Ezekiel 18:9 Leviticus 25:36 Leviticus 25:37 Nehemiah 5:1 Nehemiah 5:2 Nehemiah 5:3 Nehemiah 5:4 Nehemiah 5:5 Nehemiah 5:6 Nehemiah 5:7 Nehemiah 5:8 Nehemiah 5:9 Nehemiah 5:10 Nehemiah 5:11 Nehemiah 5:12 Nehemiah 5:13