Toward A Christian Worldview - Faith Presbyterian Church Reformed

Chapter 2: Christianity and the Basic Elements of Philosophy
Legalism, in its most consistent form, claims that law keeping, by
itself, is the savior of both man and society. It concerns itself with
external conformity to a standard of law, a standard which is always,
in one way or another, a man-made law. As Paul writes, men, “seeking
to establish their own righteousness, have not submitted to the righteousness
of God” (Romans 10:3). This form of legalism was adopted
by the Pharisees of Jesus’ day (Matthew 15:1-9; 23:1-39). It is also the
error of Pelagianism. {16} Equally false and dangerous is the semi-Pelagian
teaching of the Roman Catholic Church, that justification is a comixture
of grace and works.
Sometimes, in a less consistent fashion, legalism comes in the
form of non-biblical lists of “do’s” and “don’ts.” Other times it is
found in mere tradition. But it is always humanistic in origin. Man’s
law is set in opposition to the law of God.
Legalism implies, along with Protagoras’ assertion, that “man is
the measure” of all things. But if man is the measure of all things, then
what one man believes is as true as what any other man believes. Both
would be able to claim to be correct. So if one of them believes that
the other is wrong, then the second man is necessarily wrong. And if
the second man believes that the first is wrong, then the first man is
necessarily wrong. Hence, both are right and wrong at the same time,
which is a contradiction. And, as we have seen, that which is contradictory
must have an inescapably erroneous axiom. Jesus speaks
15. R.C. Sproul, Following Christ (Wheaton: Tyndale House, 1983), Part Four.
16. Pelagius was a fourth century British monk who propagated this system of
legalism. His teachings were staunchly opposed by Augustine.
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