Nehemiah 10:29-31

29They joined with their brethren, their nobles, and entered into a curse, and into an oath, to walk in God’s law, which was given by Moses the servant of God, and to observe and do all the commandments of the LORD our Lord, and his judgments and his statutes;1 30And that we would not give our daughters to the people of the land, nor take their daughters for our sons: 31And if the people of the land should bring wares or any food on the sabbath day to sell, that we would not buy it of them on the sabbath, or on the holy day: and that we would leave the seventh year, and the exaction of every debt.2