Why does God have to do the work of salvation?
God must do the work of salvation because it is accomplished in the invisible, spiritual realm, which human beings cannot achieve. A person cannot crucify himself or produce God's righteousness; his own righteousness is as filthy rags. Salvation therefore depends on God's work, covering believers with Christ.
Les explains that salvation is God's work because it is done in the area of the invisible, in the Spirit, and therefore cannot be accomplished by human effort. He points out that our own righteousness is nothing but filthy rags, while salvation involves God's righteousness, which is by the faith or faithfulness of Jesus Christ unto all who believe. Using the illustration of a blanket or cloak that totally covers a person, Les says that when God looks at the believer, He sees that outer covering, which is Christ. That is what it means to put on Christ: whatever God sees is not me or you, it is Christ. This happens by a work of God. Les compares it to crucifixion, noting that no one can crucify himself—he might put in the first nail, but he cannot put in the second. It is utterly impossible. In the same way, in salvation a person can do nothing; God has to do it because it is being done in the spiritual realm.