Paul saw no problem with keeping the Jewish traditions/customs or even the Law itself as long as it was kept in its proper context. It is something one chooses volitionally to do but not committed to do. Therefore, there was no need to impose this on Gentiles as it was not necessary for salvation. However, anyone, either Jew or Gentile could decide to keep the Jewish feasts and any other customs as long as they knew this was not making them any better than anyone else (1Co 8:8). After all, the Jewish feasts were just as important to Gentile Christians as to Jewish Christians: Passover was a reminder of the crucifixion of Jesus and thereby forgiveness of sins (1Co 5:7), Feast of Unleavened Bread was a reminder that Jesus Christ was a sinless sacrifice for them and that accepting Him they were now also dead to the power of sin (Ro 6:3), First Fruits was a reminder of Jesus’ resurrection from the dead and thereby a promise for their future resurrection (Ro 6:4), and Shavuot was a reminder of the gift of the Holy Spirit and the union of both Jewish and Gentile believers (Ro 10:12). Even the other feasts would be an important reminder for their future: Rosh Hashanah (New Years’ or Feast of Trumpets) would represent God not forgetting the nation of Israel as He remembers His covenant with them (Ro 11:25-26) and demonstrating that God always remembers His promises; Yom Kippur (Day of Atonement) would represent the promise of Christ’s Second Coming and the salvation of the nation of Israel (Zc 13:1; Ro 11:27); and Sukkot (Feast of Tabernacles) would represent the promise of Jesus Christ, their Messiah and Savior, setting up His earthly reign on David’s throne and dwelling with His people (both Jewish and Gentile Christians) on earth (Zc 8:3, 14:9; Rv 20:4).
While Paul was mainly focused on Gentiles, he did not forget about the Jews and would often first preach in their synagogues wherever he went (Ac 14:1, 17:2). The other disciples focused more on the Jews but also did not forget about Gentiles entirely. Much of this information is not found in the scriptures but from the Roman historian Eusebius, the Christian theologian Clement, as well as others. From these sources we find the other places that the disciples preached the gospel message. These places are countries we know today as Albania, Algeria, Crete, Cyprus, Egypt, France, Gavdos, Great Britain, Greece, Israel, Italy, Jordan, Lebanon, Libya, Malta, Morocco, Sicily, Spain, Tunisia, Turkey, and Saudi Arabia.
The apostles, other than Paul, concentrated their gospel message to the Jews who lived in Jewish colonies throughout the Roman Empire. Many of the places overlap with where Paul preached, which is not really that remarkable when one finds even in the New Testament scripture that the churches were composed of both Jews and Gentiles.
It is interesting to note that one of the main areas where there is no overlap is northern Africa. However, it makes sense for the apostles to concentrate here as this was once part of the Israeli-spawned Carthaginian Empire before being defeated by Rome at least a century earlier. Shortly before Israel was taken by Assyria, many of the Israelites fled to Carthage, which was then known as Kirjath-Hadeschath, and became a significant part of Carthage’s rise to power. Therefore, it is likely that a large contingent of Jews still lived in these areas of North Africa. This is just part of the total Jewish/Israeli population that existed in the first century AD.
From this we see that God has always cared for both Jews and Gentiles, and has a plan for both.
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