Here are some of my own definitions of some theological terms:
Propitiation: The act of God, because of His matchless love for fallen humanity, in which He took our punishment upon Himself through the offering of His Son Jesus the Messiah to die in our place, in order to fulfill His justice and anger against sin. Mercy seat.
Redemption: purchased from the slavery of sin by the precious blood of Jesus the Messiah.
Salvation: God’s gracious rescue of humans from a life of sin and death, and transferring them to a life in union with the resurrected Messiah, Jesus. It is offered to all, but given only to those who believe.
Justification: The declaration by God that one has been forgiven of their sins and thus has a right standing in God’s covenantal family because of the faithfulness of Jesus the Messiah through His death and resurrection.