Separation is the outcome of separation! When a nation (i.e., Israel in the Old Testament) or an individual (i.e., a believer in the New Testament) is set apart by the Lord, that nation (or person) has become disassociated with the rest of the world. Moses made this point in Exodus 33:16 when he said, “For wherein shall it be known here that I and thy people have found grace in thy sight? is it not in that thou goest with us? so shall we be separated, I and thy people, from all the people that are upon the face of the earth.” Separation is not something accomplished through diligence but occurs naturally after a person comes to know Christ as Saviour. Christians who remain attached to the world find little satisfaction with the things of the world or less appeal for the things of God.
Purity often involves a process. The twofold purification process in the believer's life commences at the moment of salvation. This process then progresses as the believer walks with the Lord. The individual's faith in the finished work of Christ washes away one's sin in Christ’s blood. Christ's blood cleanses completely and purifies every believer from his sin. This cleansing and purification remains forever settled between the Lord and the believer. The born-again Christian will never and can never again be any less pure in his position with the Lord. Peter confirms the positional purity when he wrote that his audience had “purified” (past tense) their souls (1 Peter 1:22). Our purity in position, settled by trusting Christ as Saviour (Titus 2:14), cannot be reversed. However, positional purity does not guarantee purity on a daily basis during our walk. The Christian's practice (his walk) must by choice remain pure.
