Aplh,Paul’s credentials as an apostle were attacked, even in his own lifetime, by those who desired to lead the church into legalism and other errant ideologies. Paul defends himself from the spurious attacks of false teachers in 1 Corinthians 9; 2 Corinthians 12; and Galatians 1.
Secondly,Jesus was obviously human (He was born, grew up, ate, slept, felt pain, sadness and fear, was tempted, and finally died), it gradually became clear to His disciples that He was more than just a man.
1)He had power over sickness, death, demons and the forces of nature (e.g. Luke 8:22-56)
2)He claimed authority over divinely given laws and institutions like the Sabbath (Luke 6:5)
3)He forgave sins. (Isaiah 43:25; Luke 5:18-25)
4)He claimed to be the final Judge of mankind (Psalm 9:7,8; Matthew 25:31,32)
5)He spoke of Himself in ways that were interpreted as claims to divinity (John 10:31-33)
6)He claimed to be the embodiment of the Father (John 14:7-10)
7)He accepted the worship of others...so wasnt just a messenger as you say. (John 20:26-29)
Yet He was clearly separate from the Father to whom he prayed.
Christians have resolved this paradox by saying that Jesus is both human and divine. But they have disagreed over the exact details of how Jesus? divine and human natures are related to each other.
For just as through the disobedience of the one man the many were made sinners, so also through the obedience of the one man the many will be made righteous. Romans 5:19