Ye shall not add unto the word. — The word, not “the words.” The word is the substance of the Law. The words in which it is expressed may be more or less. The law of Moses contains in it the germ of all revelation to the very end.
Related Commentaries of Deuteronomy 4:2
Deuteronomy 4:2
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.