'Sure' in the Bible

So the field of Ephron, which was in Machpelah, which was before Mamre, the field, and the cave which was therein, and all the trees that were in the field, that were in all the border thereof round about, were made sure

And the field, and the cave that is therein, were made sure unto Abraham for a possession of a burying-place by the children of Heth.