Paul was never chosen to be an apostle of Jesus as the other were because Paul never even saw Jesus. He self-claimed to be an apostle but the Apostles of Jesus never acknowledged him an apostle. When Paul came to Jerusalem to apply to join the Sect of the Nazarenes, the Apostles of Jesus rejected him and said he could not even be a disciple. (Acts 9:26) Regarding being the Messiah, Jesus could not have been the one as an individual. The individual is born, lives his span of life and dies. The Messiah is not supposed to die but to remain as a People before the Lord forever.
(Jeremiah 31:35-37)
Acts 9:3-9 New International Version (NIV)
As he neared Damascus on his journey, suddenly a light from heaven flashed around him. He fell to the ground and heard a voice say to him, “
Saul, Saul, why do you persecute me?”
“Who are you, Lord?” Saul asked.
“I am Jesus, whom you are persecuting,” he replied. “Now get up and go into the city, and you will be told what you must do.”
The men traveling with Saul stood there speechless; they heard the sound but did not see anyone. Saul got up from the ground, but when he opened his eyes he could see nothing. So they led him by the hand into Damascus. For three days he was blind, and did not eat or drink anything.
Oh Acts was written by apostle Luke and if you read further you will find out of Saul who later was named Paul was commissioned by the Lord Jesus Christ. In his letters to the Gentiles:
Romans 1:1
Paul, a servant of Christ Jesus, called to be an
apostle and set apart for the gospel of God—
1 Corinthians 9:1
Am I not free? Am I not an
apostle? Have I not seen Jesus our Lord? Are you not the result of my work in the Lord?
2 Corinthians 12:11
I have made a fool of myself, but you drove me to it. I ought to have been commended by you, for I am not in the least inferior to the “super-
apostles,” even though I am nothing.
You said:
The Messiah is not supposed to die but to remain as a People before the Lord forever.
(Jeremiah 31:35-37)
Jeremiah 31:35-37 New International Version (NIV)
This is what the Lord says,
he who appoints the sun
to shine by day,
who decrees the moon and stars
to shine by night,
who stirs up the sea
so that its waves roar—
the Lord Almighty is his name:
“Only if these decrees vanish from my sight,”
declares the Lord,
“will Israel ever cease
being a nation before me.”
This is what the Lord says:
“Only if the heavens above can be measured
and the foundations of the earth below be searched out
will I reject all the descendants of Israel
because of all they have done,”
declares the Lord.