The figure of the Messiah is the guarantee that guarantees the triumph of divine designs in history, the prevalence of good over evil. God's plan was to save the world for himself, for his "own son." "But when the fulfillment of time came, God sent his Son, born of a woman and born under the law" (Galatians 4: 4). The Creator now Savior.
Therefore, the promised salvation is a second creation, which is essentially divine work, because nothing that the human being can do can change his status as a sinner, subject and object of death. “But when the goodness of God our Savior was manifested, and his love for humanity. He saved us, not by works of justice that we would have done, but according to his mercy, through the washing of regeneration and renewal by the Holy Spirit ”(Titus 3: 4-5). He saved us. There is NO power in all creation that can separate a believer from Christ.
RE: Isaiah 43:2