The Old Testament reading for morning prayer today (Trinity Sunday) was from Exodus 3, including the following (Exodus 3:13-15):
But Moses said to God, ‘If I come to the Israelites and say to them, “The God of your ancestors has sent me to you”, and they ask me, “What is his name?” what shall I say to them?’
God said to Moses, ‘I am who I am.’ He said further, ‘Thus you shall say to the Israelites, “I am has sent me to you.”‘
God also said to Moses, ‘Thus you shall say to the Israelites, “The Lord, the God of your ancestors, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you”:
This is my name for ever,
and this my title for all generations.’
It’s interesting that God’s answer to the question “What is your name?” is, in essence, a double evasion.
For the Israelites to seek and obtain God’s name would be for them to try to turn God into an object, an entity; something that they could comprehend or even control. It would have been to fit God into a world they already knew: just another deity, with his own particular name and attributes.
So God gives two answers that are, on the surface, non-answers. First, “I am who I am” (or just “I am”). In other words, the first thing to know about God is that he exists, and that the nature of his existence is entirely determined in his own terms and not by reference to anything else in existence.
Second, he tells Moses to say to the Israelites:
“The Lord, the God of your ancestors, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you.”
From the translation – and I’d be interested to hear the thoughts of anyone familiar with the Hebrew original, as to whether I’m about to bark completely up the wrong tree here – it appears that it is this statement as a whole, not just the “YHWH” with which it begins, to which God is referring when he continues:
This is my name for ever…
In other words, we know God not as he is in himself, but in what he does in the world, and in particular in his sending messengers and saviours to his people – in this case Moses, but ultimately and supremely in his sending Jesus.
And even if “This is my name…” is simply referring back to the name “YHWH”, that name itself can only be understood in terms of God’s actions in and for his people.
In summary, God refuses to tell the Israelites at this stage what he is like. What they need to understand, first and foremost, is that he is, and what he does. In the same way, how we know God is, first and foremost, as we encounter him in the word and sacraments – the proclamation and making present of his actions for us in Christ – rather than through the consideration of abstract principles about him.