“Jesus Christ is the same yesterday, today, and forever. Do not be carried away with various and strange doctrines…” (Hebrews 13:8-9).
Christians of every century are to abide in the doctrine of Christ (2 John 9). Proper reverence for God’s word necessitates that no uninspired human add to or subtract from divine revelation (Deuteronomy 4:2; Proverbs 30:5-6; Revelation 22:18-19). Anyone–including an angel–who tampers with the gospel/doctrine of Christ is anathema to God (Galatians 1:6-9).
There are many Biblical reasons why false doctrine is inherently flawed. Consider the reasons implicit and employed in this inspired text
First, one of the characteristics of deity is changelessness. After reflecting upon the ephemeral nature of God’s creation (Psalm 102:25-26), the Psalmist declared, “But You are the same and Your years will have no change” (Psalm 102:27). The final prophet of the Old Testament recorded this declaration: “I am the Lord, I do not change” (Malachi 3:6).
The doctrine of Christ is God’s final and unchanging revelation of His mind and will to humanity (Hebrews 1:1-2) and we should not refuse Him who speaks (Hebrews 12:25). Therefore, the ultimate source of any doctrine at variance with Christ’s is demonic (1 Timothy 4:1).
Second, because of Christ’s changelessness, His doctrine is changeless as well. Just as Jesus will never be superceded, supplemented, or supplanted, His doctrine–the revealed New Testament–will never be either.
The inherent, fundamental flaw of all false doctrine is its implicit blasphemy of Jesus, His deity, and His perfection.
Such blasphemy is reprehensible.
