Deuteronomy 4:2

4:2 You shall not add to the word which I command you, neither shall you diminish from it, that you may keep the commandments of Yahweh your God which I command you.
-World English Bible

Other Translation

4:2 Ye shall not add unto the word which I command you, neither shall ye diminish [ought] from it, that ye may keep the commandments of the LORD your God which I command you.
-King James Version