'Sure' in the Bible

The Lord said, "The men of Judah should take the lead. Be sure of this! I am handing the land over to them."

Call judgment down on Meroz,' says the Lord's angelic messenger; 'Be sure to call judgment down on those who live there, because they did not come to help in the Lord's battle, to help in the Lord's battle against the warriors.'

Look, I am putting a wool fleece on the threshing floor. If there is dew only on the fleece, and the ground around it is dry, then I will be sure that you will use me to deliver Israel, as you promised."