No, you are not in the church of God is the point. That church was this one!
Matthew 16:17 And Jesus answered and said unto him, Blessed art thou, Simon Barjona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven. 18 And I say also unto thee, That thou art Peter, and upon this rock I will build my church; and the gates of hell shall not prevail against it.
The one that was "added" to in early Acts!
Acts 2:38 Then Peter said unto them, Repent, and be baptized every one of you in the name of Jesus Christ for the remission of sins, and ye shall receive the gift of the Holy Ghost.39 For the promise is unto you, and to your children, and to all that are afar off, even as many as the Lord our God shall call. 40 And with many other words did he testify and exhort, saying, Save yourselves from this untoward generation. 41 Then they that gladly received his word were baptized: and the same day there were added unto them about three thousand souls.
That's not the church, the Body of Christ!