Throughout history, racial ideologies have been driving forces of war, of social cohesion, of demagoguery, and of dictatorships. Race theory was central to the Nazi regime and was used by both sides in the Pacific theater of World War II. In that theater of the war, both the Japanese and the Americans claimed that the other was an inferior race.”
Among Christians, the word heresy must be used with care and precision. Not every doctrinal error is a heresy, though all doctrinal error is to be avoided. A heresy is the denial or corruption of a Christian doctrine that is central to the faith and essential to the gospel. The late theologian Harold O. J. Brown defined heresy as a doctrinal error “so important that those who believe it, who the church calls heretics, must be considered to have abandoned the faith.”
That sets the issue clearly. Premillennialists consider postmillennialists to be in error, but they do not consider postmillennialists to be heretics. Those who deny the Trinity, on the other hand, are heretics, and the believing church must consider non-trinitarians to have departed the faith. The same must be said of those who deny the full deity and humanity of Jesus Christ. Far more can be said about heresy, but the word must be used with care and accuracy.
Protestants, rightly standing with the Reformers, have insisted that justification by faith alone is also central to the gospel of Christ and essential to any proclamation of that gospel. Martin Luther, for example, considered justification to be articulus stantis et cadentis ecclesiae — the article by which the church stands or falls, and so it is.