From Anstey’s Doctrinal Definitions:
The Bible speaks of the cleansing of the Christian’s soul in three ways:
• Moral cleansing.
• Judicial cleansing.
• Practical cleansing.
1) Moral Cleansing
This is effected in a person when he is born again. The Spirit of God uses the Word of God (of which water is a figure) to communicate divine life to the soul, and the person is thereby "washed" or cleansed (John 13:10a; John 15:3; 1 Cor. 6:11). He is “clean every whit” (John 13:10b). This is a once-for-all-time cleansing, for the washing that occurs by being born again is never repeated in a person. W. Kelly’s Translation renders this as “bathed,” signifying this once-for-all washing. As a result, there is a new clean thing in the person—a new life with a new nature. By virtue of this cleansing, he is made part of the family of God, and therefore, he will never come into eternal judgment.
2) Judicial Cleansing
While moral cleansing makes a person a child of God in the family of God, it does not in itself make him a Christian. To have the distinguished place of being a Christian in the family of God, a person needs further cleansing—that which is effected by the blood of Christ (the token of His finished work) when applied by faith to the heart and conscience. This necessitates one having an understanding of the gospel of God’s grace and receiving Christ as his Saviour. This second kind of cleansing has to do with the purging of the conscience, and it is what brings a person into the full Christian position before God in Christ, whereupon he is sealed with the Holy Spirit (Heb. 9:14; Eph. 1:13). Thus, a Christian is one who has been “washed” with water (John 13:10a; Heb. 10:22) and “washed” in the blood of Christ (1 John 1:7; Rev. 1:5). Mr. Darby distinguished these two washings as: "moral cleansing" and "judicial cleansing" (Collected Writings, vol. 13, pp. 236, 238).
Thus, there are two cleansing agents needed to make a person a Christian—water and blood. The water deals with our unclean state and the blood deals with our guilt—our defiled conscience. Old Testament saints were born again, and thus cleansed by the water of the Word of God, but they did not have a judicial cleansing of the conscience effected by the blood, because Christ had not accomplished redemption yet. Consequently, their consciences were not purged, as Christians’ consciences are (Heb. 9:14; 10:2). This can be seen in the fact that they lived with a certain degree of fear that their sins would be brought up by God for judgment (Psa. 25: 11, 18, etc.).
In John 19:34, the “blood” is mentioned before the “water,” because it is recording the historical fact; whereas in 1 John 5:6-8, the water is put before the blood, because it is referring to the order of its application in the lives of men. One is God's side and the other is man's. Before the eye of God the blood must come first. It is required in order for men to be blessed. All of God's workings by His Word and His Spirit in new birth are dependent upon, and are in view of, Christ’s entering the world and paying the price for sin—of which the blood speaks (Heb. 9:22). J. A. Trench said, "'One of the soldiers with a spear pierced His side, and forthwith came there out blood and water' (John 19:34). This is the historic order, and in it the blood comes first, as the basis for everything for God's glory and our blessing. In the order of application to us, as John in his epistle (1 John 5:6) puts it, the water comes first: 'This is He that came by water and blood...and it is the Spirit that bears witness'" (Scripture Truth, vol. 1, p. 22).
3) PRACTICAL CLEANSING—There is a third kind of cleansing in the New Testament that has to do with the water of the Word of God being applied to the walk and ways of believers (John 13:10b; Eph. 5:26). This has to do with practical cleansing. We are to let the Spirit of God apply the Word of God to our hearts and consciences in our daily reading of the Scriptures, and if He brings to light something in our lives that is inconsistent with the holiness of God, we are to judge ourselves, and get that thing out of our lives, whereupon we are cleansed in a practical way. When we bring our lives into accord with the practical injunctions of holy living in the Word of God, practical cleansing results. While moral and judicial cleansing are effected for us by God as a once-for-all thing, practical cleansing is the responsibility of the Christian. It should go on continually in a believer’s life, whereupon communion with God will be uninterrupted.