In his witness to Agrippa, Paul included the resurrection of Jesus from the dead.
Do you not realize how relevant the resurrection is to the Gospel of Christ? 1 Cor 15:17 tells us And if Christ be not raised, your faith is vain; ye are yet in your sins.
If you do not recognize how vital the resurrection is, you've got some studying to do because you might not be born again, and if you're not born again it explains why you do not recognize that what we have in our day and time is "something better".
Of course Paul taught the resurrection of Jesus Christ, that is the central part of our faith.
However the Gospel of Jesus Christ, that He preached and His Apostles were sent to preach is -
Repent for the kingdom of God is at hand.
The way we obey the Gospel command repent, is to confess Jesus Christ as Lord.
Repent means to turn to God.
If you are called to
turn to God, then by default you are
called to turn from Satan as your lord.
The way that your express this obedience of faith, concerning the Gospel is to
confess Jesus as Lord.
This is what grants the
believer/obeyer of the Gospel, the forgiveness of sins.
Peter replied, “
Repent and be baptized, every one of you, in the name of Jesus Christ for the forgiveness of your sins. And you will receive the gift of the Holy Spirit.
Acts 2:38
Peter did not say "repent of your sins".
A person can not "stop sinning" without the born again new Nature empowered by the Holy Spirit.
The way we are granted this, is by repenting, which means turning away from Satan and his kingdom, and turning to God, and confessing Jesus as Lord.
This is plainly what the Lord Jesus Christ taught to and commissioned Paul to do.
15 So I said, ‘Who are You, Lord?’ And He said, ‘I am Jesus, whom you are persecuting. 16 But rise and stand on your feet; for I have appeared to you for this purpose, to make you a minister and a witness both of the things which you have seen and of the things which I will yet reveal to you. 17 I will deliver you from the
Jewish people, as well as
from the Gentiles, to whom I now send you, 18 to open their eyes,
in order to turn them from darkness to light, and from the power of Satan to God, that they may receive forgiveness of sins and an inheritance among those who are sanctified by faith in Me.’
Acts 26:15-18
Repent is about being transferred from the kingdom of darkness to the kingdom of God.
It's about changing who you serve, as your Lord.
The Gospel of the kingdom is about changing the kingdom your are in, by changing the lord you serve.
The Gospel is God's call to humanity, to "come out of hiding", in darkness, and to come into the light, the kingdom of light.
JPT