The witness of men to the Gospel may be valuable, if its doctrines are purely taught, and the ordinances rightly administered.  But the testimony of men is always a shaky foundation upon which to build our faith.  In reality, man’s testimony only has weight insofar as it corresponds to the doctrine of God’s word.  The testimony of God is far greater.  We have just described the testimony of God, as it relates to the cleansing power of the Holy Spirit in regeneration and sanctification, and of the blood of Christ as regards our guilt and the purifying of our consciences.  But all of this is connected to the fundamental doctrines of the Gospel, which involve Jesus Christ in His sacred person and His glorious work.  John would forever be pointing us back to Christ, in Whom alone salvation is found.  We must believe that He alone is God’s Messiah, and that He is uniquely God’s only begotten Son, of one essence with the Father.  We must believe that only through His blood may our sins be forgiven.  This is the witness of God regarding His Son, which all men must believe if they would be saved.  Upon believing, we are sealed with that Holy Spirit of promise, Who is the witness within us that we truly are the children of God.