For centuries, the Jewish people had been taught not to associate with Gentiles. This was based on the Bible (see Is 52:11). After Pentecost, the Jewish Christians were told that the Gentiles had been given the Holy Spirit (Acts 15:8). This indicated that Jewish Christians should accept Gentile Christians as brothers and sisters (see Eph 3:6). James, the leader of the Jerusalem church, said that this was based on the Bible (Acts 15:15-16; Am 9:11). Thus, there were two very different, authoritative, seemingly contradictory interpretations of the Bible on a point of extreme significance. What was the truth? What was God's will?
The early Christians were able to rise above their cultural biases and personal limitations because they were in submission to the Church. They were in submission to their local church leaders, who were in submission to Peter, the apostles, and the elders in Jerusalem (see Acts 15:2). Only in this way did the early Christians understand the Biblical revelation concerning the Gentiles' part in God's plan of salvation.
Private interpretation of the Bible did not work in critical situations of the New Testament Church. Private interpretation does not work today as very holy and learned people disagree on such important matters as the meaning of the Eucharist, the indissolubility of marriage, the nature of authority in the Church, the importance of liturgy, the role of women in the Church, etc. We need to be in submission to an authoritative Church with one final authority, the Pope. Otherwise, we cut ourselves off from the fullness of God's revelation.