Self-judgment is the believer’s deliberate agreement with the Holy Spirit about sin. By an act of the will we say to God, “Yes, I want this thing separated from me. I will be done with it. I renounce it”. By an act of faith, we count on what was already accomplished at the Judgment of the Cross and make it ours in present experience. Redemption is not automatic; at every point it requires our cooperation with God who is working in us. When we judge ourselves, His authority is behind it to make it effective in working permanent change.
Likewise reckon ye also yourselves to be dead indeed unto sin, but alive unto God through Jesus Christ our Lord (Romans 6:11).
Self-judgment is our present application of the past judgment finished at Calvary.
Self-judgment is impossible without the knowledge that Christ completed His work of judging our sin on the Cross. Flesh cannot judge flesh, however. We must allow the Holy Spirit to apply His power to our lives as we actively ask Him to eliminate all in us that is displeasing to God. Self-judgment requires our full consent to turn away from sin and to forsake all that the Holy Spirit makes known to us as displeasing God.
. . . but if ye through the Spirit do mortify the deeds of the body, ye shall live (Romans 8:13).
Self-judgment is our agreement with the Holy Spirit’s diagnosis of our need.
We cannot reform ourselves. Our hearts are deceitful and cannot be analyzed apart from the light God gives. The Holy Spirit makes us aware of our need as God views it and enables us to agree with Him. Then He is free to apply liberating judgment.
Search me, O God, and know my heart: try me, and know my thoughts: And see if there be any wicked way in me, and lead me in the way everlasting (Psalm 139:23, 24).
Self-judgment is a preventative from experiencing God’s chastening.
If we examine ourselves in the light of God’s Word and with the Spirit's convincing, and correct our behavior accordingly, God will not have to chasten us in order to stimulate needed changes. But if we neglect to correct ourselves, God will deal with us as a faithful Father. He will bring pressure to bear upon us to effect the changes He desires in us. To put it simply, “If we don’t act, God will”.
Furthermore we have had fathers of our flesh which corrected us, and we gave them reverence: shall we not much rather be in subjection unto the Father of spirits, and live? For they verily for a few days chastened us after their own pleasure; but he for our profit, that we might be partakers of his holiness (Hebrews 12:9, 10).