"Jesus has become a surety of a better covenant" (Hebrews 7:22). A surety is a guarantee. Jesus is the guarantee of a better covenant. Jesus is the Shepherd, and we are the sheep, through the blood of the everlasting covenant. He works in us what is pleasing to God (Hebrews 13:20-21). Faith is sure in Christ as our surety.
Faith is sure through promises guaranteed in Christ. The New Covenant makes four promises to every believer, guaranteed through Jesus Christ (Jeremiah 31:31-34; Hebrews 8:7-13). These promises are: (1) God will put His laws in your mind; (2) God will be your God and we are His people; (3) We will all know the LORD; (4) God will forgive your sins and remember them no more.
Faith is sure through promises guaranteed in the gospel of Christ (1 Corinthians 15:1-4). He died for our sins. He is risen from the dead for our justification. We are children of God by faith in the Lord Jesus (Galatians 3:26).
Faith is sure through Jesus our Mediator of the New Covenant. He prays for believers that God the Father will "keep them from the evil one" (John 17:15). This is the present day ministry of Jesus, as every believer's High Priest (Hebrews 7:20-25). Jesus shall return to glorify all who believe in him (1 John 3:2). That's the New Covenant guaranteed in the Lord Jesus Christ.
