Many versions/denominations of "Christianity"

As I keep repeating, only the FIRST version of Christianity, the one by Jesus, was authorized. Many additional versions were invented after Jesus had been crucified by the Romans, but these versions nevertheless use the name "Christianity" and (most? all?) of their members think they are Christians. The only Christians are those people who at all times follow Jesus and his lifestyle. See Acts 2 and Acts 4 for a partial description of that community, an artificial "family".