To hold (someone) hostage until a ransom is paid.
To liberate by payment of a ransom.
To recover ownership of something by buying it back.
To clear, release from debt or blame
To set free by force.
To save, rescue
To repair, restore
To save from a state of sin (and from its consequences).
To restore the honour, worth, or reputation of oneself or something.
To reform, change (for the better)
To expiate, atone (for)
To convert (some bond or security) into cash