Paul and Peter Identified Themselves in Their Own Epistles

"That ye be not soon shaken in mind, or be troubled, neither by spirit, nor by word, nor by letter as from us, as that the day of Christ is at hand" (2 Thess. 2.2). "The salutation of Paul with mine own hand, which is the token in every epistle: so I write" (2 Thess. 3.17).

Peter identified himself 2 Pet. 1.1, "Simon Peter, a servant and an apostle of Jesus Christ, to them that have obtained like precious faith with us through the righteousness of God and our Saviour Jesus Christ." Peter wrote, "For we have not followed cunningly devised fables, when we made known unto you the power and coming of our Lord Jesus Christ, but were eyewitnesses of his majesty. For he received from God the Father honour and glory, when there came such a voice to him from the excellent glory, This is my beloved Son, in whom I am well pleased. And this voice which came from heaven we heard, when we were with him in the holy mount." (2 Pet. 1.16-18). Peter was one of the Apostles who saw Jesus resurrected.

"The Pastoral Epistles (1-2 Timothy and Titus) all claim to be by Paul and communicate many details from his life, which would be quite deceptive if Paul did not, in fact, write the letters. Some of the authors may have employed a secretary (amanuensis) to assist them in writing, which might account for some of the stylistic differences in the letters. Still, each letter would have been carefully dictated and reviewed by the apostolic author."

http://www.jesus.org/early-church-hi...-epistles.html