If Christ's whole life was vicarious, every aspect of piety was on our behalf and in our place. It is his faith, his obedience, his faithfulness, his prayer which avails for us. As our great high priest, he offers up worship and praise acceptable to a holy God, the fruit of a life of perfect faithfulness, flawless and pure. By virtue of that perfect intercession we are acceptable to God, having been brought by the grace of God to entrust ourselves into his hands. We therefore have full and open access to God precisely because Christ himself has full and open access to God. It is fully and only in Christ's mediation that we have such confidence to know that the way is open.
Robert Letham, The Work of Christ (Leicester: IVP, 1993), p. 118