Sur means to turn aside, depart, remove, or put away. It appears about 300 times. It describes physical departure, moral deviation, and the act of removing sin or evil from one's midst.
God commands Israel to sur (put away) foreign gods and evil from their midst. 'Depart from evil' is a core ethical command. Yet sur also describes Israel's tendency to 'turn aside' from God's way — the perennial problem of unfaithfulness that drives the prophetic message.