Why is the concept of covenant important in understanding salvation?

The concept of covenant is central to Reformed theology, illustrating how God has benevolently initiated relationships with His people throughout history. Zechariah reflects on the covenant made with David in his prophecy, recognizing that Christ’s coming as the horn of salvation fulfills this promise. This understanding leads to the conclusion that salvation is not something we achieve on our own, but a gracious gift bestowed upon us due to God’s unchanging will to redeem a particular people—His covenant community—through Christ’s work on the cross.