The Westminster Shorter Catechism
Q35. What is sanctification?
A. Sanctification is the work of God’s free grace,[1] whereby we are
renewed in the whole man after the image of God,[2] and
are enabled more and more to die unto sin,
and live unto righteousness.[3]
[1] 2 Thessalonians 2:13; [2] Ephesians 4:23–24; [3] Romans 6:4, 6; 8:1.
To a great majority of Christians, sanctification refers to the idea of spiritual renewal and the endowment of moral and spiritual qualities on man. Some have even equated sanctification with feeling spiritual. This, however, is not the biblical idea. Rather, sanctification speaks of making a person holy; and holiness in this case is defined with respect to the degree in which a person is like God in His moral perfection.
It is described in our answer as a work
rather than an act as with
justification and adoption (WSC
33–34) because it is a continuous and gradual operation of God the Holy Spirit
in the soul of the justified sinner. Paul tells us that we are chosen “to
salvation through sanctification of the Spirit” (2 Thes 2:13). Paul is of
course speaking of salvation as a process leading to our glorification at the
end of this life’s journey. It is called “the work of God’s free graceּ not
only because it is the work of God from first to last, but also because we do
not deserve it at all.
Positively, sanctification consists in our being “renewed in the whole man
after the image of God.” The word “renewed” is used to suggest that we are
being restored to the state that Adam and Eve were in, when they were first
created in the image of God in knowledge, righteousness and holiness.
Negatively, sanctification consists in our being “enabled more and more to die
unto sin, and live unto righteousness.” In other words, we are more and more
purified from the pollution of sin and made more and more to hate sin, while at
the same time growing to love righteousness and finding it more and more in our
nature to practise holiness.
A few things need to be highlighted about sanctification. (a) God, and not man,
is the author of sanctification, but this does not mean that man is entirely
passive in the process. He can and should co-operate with God in the work of
sanctification by the diligent use of the means that God has placed at his
disposal (e.g., 2 Cor 7:1). (b) Sanctification, unlike justification is not a
legal act. It is a moral activity in which the sinner is made to conform more
and more to the image of God. (c) It is usually a lengthy process that lasts a
lifetime without achieving perfection in this life. (d) It is completed at
death in so far as the soul is concerned, and at the resurrection in so far as
the body is concerned (Phil 3:21).