The Signs of Self-Deception are Many. When a professor of religion is wise and prudent in worldly matters, but not shrewd or discerning in the things of religion, he is deceived. "All thy children shall be taught of the Lord." (Isa. 54:13) If we lack spiritual discernment, we lack the Holy Spirit; and "if any man have not the Spirit of Christ, he is none of his. " (Rom. 8:9) Jesus Christ laid down gross spiritual blindness as a mark that men were not of God. (Matt. 16:2;3.)