Here are a few of the summary statements by New Testament witnesses. There are at least another 5 or so with the same feature. No writer urges obedience to the law or reliance on prophets.
Finally, my brothers, rejoice in the Lord. To write the same things to you is no trouble to me and is safe for you. Philippians 3:1
Finally, then, brothers, we ask and urge you in the Lord Jesus, that as you received from us how you ought to walk and to please God, just as you are doing, that you do so more and more. 1 Thessalonians 4:1
Finally, all of you, have unity of mind, sympathy, brotherly love, a tender heart, and a humble mind. 1 Peter 3:8
How could the guardians of God’s saving revelation not proclaim the whole duty of man?