Deut 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. (c.f Deut 12:32)
Deut 10
11 For this commandment which I command you this day, it is not too hard for you, neither is it far off. 12 It is not in heaven, that you should say, Who shall go up for us to heaven, and bring it to us, and make us to hear it, that we may do it? 13 Neither is it beyond the sea, that you should say, Who shall go over the sea for us, and bring it to us, and make us to hear it, that we may do it? 14 But the word is very near to you, in your mouth, and in your heart, that you may do it.