'Oath' in the Bible

Then said they, We will restore them, and will require nothing of them; so will we do as thou sayest. Then I called the priests, and took an oath of them, that they should do according to this promise.

They clave to 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;