'Purchase' in the Bible

So after consulting together they spent the money in the purchase of the Potter's Field as a burial place for people not belonging to the city;

By your patient endurance you will purchase your lives.

in order to purchase the freedom of all who were subject to Law, so that we might receive recognition as sons.

who gave Himself for us to purchase our freedom from all iniquity, and purify for Himself a people who should be specially His own, zealous for doing good works.