Page 225,

Now let us especially notice what the essence of mortal sin is. To do so will enable us to know how to keep ourselves away from it so that (1) our flesh may not be corrupted, (2) we may not forfeit the blessing of being raptured before death, or (3) we may still finish the Lord’s appointed work before our days are fulfilled and we die, if He should tarry and we must pass through the grave. May we say that because of their negligence in this matter quite a few of God’s children have had their years shortened and their crowns lost. Many of God’s workers, had they given attention to this, might yet be serving the Lord.