two gospels?

Paul explicitly calls himself an apostle of the Gentiles (=nations) a number of times. When it really comes down to it, Paul appeals to Caesar as a Roman, and therefore as a Gentile (Acts 25:11). This is in contrast to the twelve apostles who came from Israel and were also sent to the house of Israel (Matt. 10:6). They are emphatically not sent to the nations (Matt.10:6)

the gospel of the circumcision and the gospel of the uncircumcision
But it doesn’t stop there. There is also a difference in the message. Most translations don’t make it clear, but in Galatians 2 Paul makes a distinction between the gospel of the uncircumcised (that is, the nations that have the foreskin because they are not circumcised) and the gospel of the circumcision (that is, the Jews). Below are the relevant verses. The parenthetical sentences in verses 8 and 9 have been omitted for readability.

Galatians 2
6 …for those who were respected (>Peter, James and John, 1:18,19; 2:9) imposed nothing on me.
7 But on the contrary, when they saw that to me was committed the gospel of the uncircumcision, as to Peter that of the circumcision;
9 …they gave me and Barnabas the right hand of fellowship, that we should go to the nations, and they to circumcision.

the gospel of circumcision
Most translations change from to before, as if it were just for a different target group, but the original text is clear. There is a second case twice and therefore: the gospel of the uncircumcision and the gospel of the circumcision. The twelve apostles, including James, Peter (Cephas), and John (Gal.2:9) preached the gospel of the circumcision. What is that gospel?
It is the message that if Israel would repent, the Messiah would come and the promised Kingdom would dawn. Peter shows this beautifully in one of his speeches.

Acts 3
19 Consider therefore, and turn, that your sins may be blotted out, that times of refreshing may come from the presence of the Lord,
20 and He will send Christ Jesus, who is predestined for you.
21 Whom heaven must receive until the time of the restoration of all things, which God hath spoken by the mouth of all his holy prophets from the aeon.

Paul, the 13th apostle, was sent to deliver a different message. God had revealed to him that Israel would not repent. They would reject the message of the resurrected Christ and the Kingdom would be taken from them. In the Gospels we already find this in a hidden way as the Lord Jesus in parables speaks of the Jewish people, for example in Matthew 21 (see especially verse 43).

Israel aside
Israel would not receive the message and Paul knew from the beginning that the Jewish people would not receive his testimony (Acts 22:18). At this Israel was set aside and salvation went to the nations (Acts 13:46-47, 22:21, 28-28).

A people from among the nations
In our time, an intermediate and previously hidden period (Eph 3:5), God is gathering to himself a people from the nations for his name (Acts 15:14). The period in which God does this is called the mystery. There is no visible kingdom and no visible Messiah on the throne in Jerusalem today, as promised in the Old Testament scriptures, but the kingdom is hidden and the Messiah is in heaven (Col 3:1-4).

In the near future God will pick up the thread again with his people Israel.The gospel of the kingdom will then become topical again and will be preached throughout the world by a faithful Israel (Matt24:14). Now,however, Christ is hidden among the nations.

Colossians 1
27 To them God will make known what are the riches of the glory of this mystery among the nations: Christ among you, the hope of glory.

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