Herman Bavinck on the essence of error

In the light of reading Alister McGrath's book on Heresy (see my review), I was interested to come across this thought from Herman Bavinck,

Now in the confession of the Trinity we hear the heartbeat of the Christian religion: every error results from, or upon deeper reflection is traceable to, a departure in the doctrine of the Trinity. (Reformed Dogmatics Volume 2: God and Creation , Baker Academic, p. 288, 2006

According to Luther, "The cross tests everything".  But the cross only functions as the definitive revelation of God and an act of redeeming grace in the context of the doctrine of the Trinity. If Christ was not God the Son, his sacrificial death did not disclose the fullness of God's love for the world. If Christ was not God the Son, his sacrificial death would not have been sufficient to atone for the sins of the world.

As the New Testament bears witness, Calvary involved the whole Trinity. Christ the Son offered himself to God the Father through the eternal Spirit (Hebrews 9:14). As such the cross tests everything. 

What we believe concerning God and ourselves must be assessed in the light of the saving work of the triune God at the cross. Arguing from resolution to plight, that it took the death of the Son of God in his humanity to save us demonstrates how how seriously God takes sin. Arguing from plight to resolution, that for us to be saved the Son of God had to take a human nature and die demonstrates that we could never hope save ourselves. God commends his love to us in that while we were yet sinners, Christ died for us and God's love is shed abroad in our hearts by the Holy Spirit whom he has given us, Romans 5:8, 5. 

Heresy distorts the doctrine of God and devastates the doctrine of salvation. A low view of Christ will lead to a light view of sin and a light view of sin will lead to a low view of Christ. As John Owen once wrote, "A Socinan Christ for a Pelagian man". We believe in nothing less than a Nicean Christ for an Augustinian man.