While biblically minded Christians confess this in theory, do they always embody it in practice? In reality, we can unintentionally fall into the same error as Marcion by functionally “taking away” from the words of Scripture. How so? By habitually focusing on only certain parts of the Bible and ignoring others. When we regularly skip past the extensive genealogies of 1 Chronicles 1–9, for example, or the detailed ritual instructions in Leviticus, we have, for all intents and purposes, become “mini Marcionites” who have cut out a part of Scripture.
Mormons, Jehovah’s Witnesses, Christian Scientists—these and other non-Christian religions claim to accept the Bible as divine revelation, but they supplement it with additional revelatory texts or traditions that wind up taking precedence over Scriptural teaching. In other words, people are adding to God’s revelation of the Old and New Testaments. A mirror image of this phenomenon is people’s taking away from the books of the Bible. The early heretic Marcion is notorious for rejecting the Old Testament and many books of the New Testament and thus holding to only a portion of the New Testament as authoritative Scripture. Whether by addition or subtraction, the whole truth of God’s Word is compromised.
The Bible repeatedly warns us against this temptation: “You shall not add to the word that I command you, nor take from it” (Deut. 4:2; 12:32); “And if anyone takes away from the words of the book of this prophecy, God will take away his share in the tree of life and in the holy city, which are described in this book” (Rev. 22:19).