Why is the concept of new covenant important for Christians?

The new covenant, fulfilled in Jesus Christ, signifies a dramatic change from the old covenant practices, including the sacrificial system that only permitted the high priest to enter the Holy of Holies once a year. With Christ's sacrificial death, the veil of the temple was torn, granting all believers access to God's presence. This new covenant is characterized by grace, forgiveness of sins, and a direct relationship with the Father, allowing us to approach Him without fear as His children.