You have to remember that the first converts to “The Way” remained distinctly Jewish: following Mosaic law, Temple traditions and dietary customs. They continued to go to Synagogue on the Sabbath (Saturday) and then on the first day of the week (Sunday) they met in each other's homes to: baptize, a reading from the memoirs of the apostles, hear a message from the leader, sharing in the Lord's Supper and singing hymns.

During Paul’s second visit to Jerusalem, he meets with the “pillars” of the Jerusalem church: James, Peter, and John. They accepted Paul and his ministry to the Gentiles. Paul went to the apostles and elders about whether Gentiles were to be circumcised. While Peter spoke and gave his response to the matter - James spoke and pronounced his judgment on the matter.

After James’ judgment, the apostles and elders made a decision on the matter sending a letter with Paul from “The apostles and elders”. Only after Paul’s missions to Antioch (Acts 11:26) did the body of believers even begin being called Christians. After the Incident at Antioch and the Council in Jerusalem (approximately 50AD, see Acts 15; Gal. 2) did separation from Judaism even begin to become apparent.

So at this point there is a body of believers e.g. universal Christian Church confessing faith in Jesus.