How do we know that Christ is all in salvation?

The assurance that Christ is central to salvation stems from the belief that being 'taught of God' enables us to see His grace and the necessity of Christ in our lives. Romans 8:30 indicates that those whom God foreknew, He also predestined to be conformed to the image of His Son. This transformation is a work of God alone, providing believers with faith to apprehend the truth that Christ represents our righteousness and the fulfillment of the law on our behalf. Thus, our certainty in Christ's sufficiency is drawn not from human decision but from divine illumination and calling.