that which we have seen and heard we declare to you, that you also may have fellowship with us. Yes, and our fellowship is with the Father, and with his Son, Jesus Christ.
And our fellowship is with the Father, and with his Son Jesus Christ ... Oneness with God in Christ is the basis of Christian fellowship, and it cannot exist without it.  That is why the doctrinal and ethical nature of the Christian message should continually be stressed from the pulpit; because, in this essential basis is the principle of cohesion that binds Christians first to God in Christ and then to each other.  Any congregation or church which depends upon a superficial social camaraderie to replace the word and doctrine as its cohesive power blunders fatally.  If there would be fellowship, first let the heresies be denied and thwarted and the ethical behavior of Christians restored.  This was exactly John's purpose in this letter.