'Alert' in the Bible

Be alert so there is no man, woman, family, or a tribe whose heart is turning away from the LORD your God to go and serve the gods of those nations. Be alert so there will be no root among you that produces poisonous and bitter fruit,

telling them, "Pay attention now! You are to set up an ambush around the city. Don't go very far from the city, and all of you remain on alert.