Augustine called the Ten Commandments “your sum of 3 and 7 – a golden harp of ten strings”. The first three are toward God, and the final seven are toward others – and 3 and 7 are the “perfect” numbers. These commandments serve as the moral backbone for any functioning society. No other law or constitution can replace them.

But here I would like to look at what bookends the “Ten Words”. First, they presume redemption – v. 2. The people who can obey these have been redeemed from the darkest of slavery, by the God Who commands them. He owns this people, for their good, for a Promised Land.  

But He Who speaks is Himself awesome power. These commandments are given at Mt. Sinai, which is covered in the greatest of power that they would recognize – the power of nature – thunder and clouds and lightning. Today, we might instead require the power of a hot supernova, or the worst nuclear explosion – but that would kill us. Just as the Israelites fear will happen to them, v. 19.

Into this fear, Moses makes this seemingly paradoxical command: “Do not fear, for God has come to test you, that the fear of him may be before you, that you may not sin.” (emphasis mine) The word “test” implies a trial, that is meant to both expose the people’s hearts and change them – God means to produce in them the right heart stance, that will enable them to obey the Ten Words.

Which requires the right fear. So what does it mean, to not fear, in order to fear? The sense seems to be, don’t be consumed by fear, and run from Me, and become separated from Me. Stay in my presence – remember, I bought you, out of Egypt – your life is found in my presence. But stay in my presence with a fear that befits Who I Am – a God of awful, incredible power, that if you really experienced it, you’d be wiped out in a flash. Stay in My presence, with appropriate fear of Who I really am.

That you may obey my Words. 

So then, how? How are they to not to be totally overcome with fear, and stand in the presence of such an awe-fully powerful Lord? 

They – we – need a mediator, v. 20. Moses draws near to the Lord, on behalf of the people, who stand back, but do not flee. He prefigures a perfect Moses, a better Mediator, who brings us not to Sinai, but Who speaks to us from our Home – New Zion (Heb. 12:18-24).