We're looking at a different "Ex" word today. (And it's not a televised singing talent competition)

The Hebrew verb "hayah" means to "be", "become", "happen" or "occur". God uses this verb to introduce himself using this simple yet powerful construct. "I AM who I AM." He uses the imperfect tense in Hebrew which implies actions that that are not completed or actions that occur in the present or future.

And so we get:

"I AM and will always BE!"
"I AM the constant one!"

"I AM and not I WAS: You can't contain me or pin me down or put me in a box."

In uncertain times He is the the One whose "constancy in the present"
makes all the difference. He is not "rock" or "mountain" He is always more. And although the Psalmist will say "God is my Rock" he expands it with other descriptions like "refuge" and "strong tower" simply indicating that there is never one single phrase that can contain God.

He calls Himself "I AM." No matter where
you are or what trouble you are in: "I AM!"

It is this same verb that forms the root of the Old Testament's
favourite unique name for God: Yahweh (translated by some as Jehovah)
which is the 3rd person form of "hayah" and means "He IS."

People asked the Israelites "Who's your God?"

They would answer "Yahweh! - He, the One who IS!"

When I was a teen, there was a Swedish Gospel Band "Edin Adahl" who sang a song entitled "X-Factor." In the chorus they sang:
You are the X-Factor, eternal life reactor, You are the X-Factor.
You put my heart in motion, activate my inner section,
You are the X-Factor!

I like the idea behind the song. God is much more than a constant
and He is more than simply a variable (small "x") He is the "(capital) X
factor" - He is the "Constant-Variable" that brings life, change and
transformation. Introduce the "X" into any equation and the equation
becomes dependent on X.

God IS.

And when He is in the room, things will change!

Moses said to God, "Suppose I go to the Israelites and say to them, 'The God of your fathers has sent me to you,' and they ask me, 'What is his name?' Then what shall I tell them?" God said to Moses, "I AM WHO I AM. This is what you are to say to the Israelites: 'I AM has sent me to you.' " (Exodus3:13-14)