'Curse' in the Bible

They were united with their brothers, their rulers, and put themselves under a curse and an oath, to keep their steps in the way of God's law, which was given by Moses, the servant of God, and to keep and do all the orders of the Lord, our Lord, and his decisions and his rules;

Because they did not give the children of Israel bread and water when they came to them, but got Balaam to put a curse on them: though the curse was turned into a blessing by our God.