Systematic Theology, by Louis Berkhof - New Leaven

IV. The Dual Aspect of the Covenant
In speaking of the contracting parties in the covenant of grace it was already
intimated that the covenant may be considered from two different points of view. There
are two different aspects of the covenant, and now the question arises, In what relation
do these two stand to each other? This question has been answered in different ways.
A. AN EXTERNAL AND AN INTERNAL COVENANT.
Some have distinguished between an external and an internal covenant. The
external covenant was conceived as one in which a person’s status depends entirely on
the performance of certain external religious duties. His position is entirely correct, if he
does what is required of him, somewhat in the Roman Catholic sense. Among Israel this
covenant assumed a national form. Perhaps no one worked out the doctrine of an
external covenant with greater consistency than Thomas Blake. The dividing line
between the external and the internal covenant was not always represented in the same
way. Some connected baptism with the external, and confession of faith and the Lord’s
Supper, with the internal covenant; others thought of baptism and confession as
belonging to the external covenant, and of the Lord’s Supper as the sacrament of the
internal covenant. But the trouble is that this whole representation results in a dualism
in the conception of the covenant that is not warranted by Scripture; it yields an external
covenant that is not interpenetrated by the internal. The impression is created that there
is a covenant in which man can assume an entirely correct position without saving faith;
but the Bible knows of no such covenant. There are, indeed, external privileges and
blessings of the covenant, and there are persons who enjoy these only; but such cases
are abnormalities that cannot be systematized. The distinction between an external and
an internal covenant does not hold.
This view must not be confused with another and related view, namely, that there is
an external and an internal aspect of the covenant of grace (Mastricht and others).
According to this some accept their covenant responsibilities in a truly spiritual way,
from the heart, while others accept them only by an external profession with the mouth,
and therefore are only apparently in the covenant. Mastricht refers to Judas Iscariot,
Simon the sorcerer, those who have temporal faith, and others. But the trouble is that,
according to this view, the non-elect and non-regenerate are merely external
appendages to the covenant, and are simply regarded as children of the covenant by us
because of our short-sightedness, but are no covenant children at all in the sight of God.
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