Nehemiah 10:28-31

28Then the rest of the people—the priests, Levites, gatekeepers, singers, Temple servants, and all who had separated themselves from the pagan people of the land in order to obey the Law of God, together with their wives, sons, daughters, and all who were old enough to understand—

29joined their leaders and bound themselves with an oath. They swore a curse on themselves if they failed to obey the Law of God as issued by his servant Moses. They solemnly promised to carefully follow all the commands, regulations, and decrees of the Lord our Lord:

30“We promise not to let our daughters marry the pagan people of the land, and not to let our sons marry their daughters.

31“We also promise that if the people of the land should bring any merchandise or grain to be sold on the Sabbath or on any other holy day, we will refuse to buy it. Every seventh year we will let our land rest, and we will cancel all debts owed to us.