Paul’s purpose was to show that the ancient prophets did not have this position of trust in God’s eyes, because theirs was a preparing ministry. Commentary on Paul’s Epistles.
And such trust have we through Christ to God-ward. The Greek word used here, denotes that confident conviction which makes the mind strive to attain some difficult end that it longs for, as though it were certain of success. Such is the confidence which is inspired into the Saints by the Holy Spirit enabling them to work miracles or other heroic works of virtue. This confidence God is wont to demand as a fitting disposition, and to give beforehand, both in him who performs and in him who receives the benefit of the miracle or other Divine gift, in order that the soul may, by this gift, expand and exalt itself, and become capable of receiving Divine power. S. Paul says in effect. "This confident persuasion that you are our epistle, written by the Spirit of the living God, we have before God through the grace of Christ; we have hope and sure confidence in God that, as He has begun, so will He finish this epistle by His Spirit." In the second place this trust is the confidence S. Paul had...
The apostle Paul, after describing in a few words the benefits of God, states in conclusion: “And for such offices, who is sufficient?” Whence he also says in another place: “Such is the assurance we have through Christ toward God. Not that we are sufficient of ourselves to think anything, as from ourselves, but our sufficiency is from God. He also it is who made us fit ministers of the new covenant, not of the letter but of the spirit; for the letter kills, but the spirit gives life.” Do we still dare to boast about the free will and treat with insult the benefits of God the Giver, when the chosen vessel [Paul] also writes very clearly: “But we carry this treasure in vessels of clay, to show that the abundance of our power is God’s and not ours”? Against the Pelagians
