God Is Self-Existent.
And God said to Moses, “I AM WHO I AM.” And He said, “Thus you shall say to the children of Israel, ‘I AM has sent me to you.’” Exodus 3:14 NKJV
A name that denotes what he is in himself: I am that I am. This explains his name Jehovah, and signifies, that he is self-existent he has his being of himself, and has no dependence upon any other: the greatest and best man in the world must say, By the grace of God I am what I am but God says absolutely--and it is more than any creature, man or angel, can say--I am that I am. Being self-existent, he cannot but be self-sufficient, and therefore all-sufficient, and the inexhaustible fountain of being and bliss.
That he is eternal and unchangeable, and always the same, yesterday, to-day, and for ever he will be what he will be and what he is see Revelation 1:8.
That we cannot by searching find him out. This is such a name as checks all bold and curious enquiries concerning God, and in effect says, Ask not after my name, seeing it is secret, Judges 13:18; Proverbs 30:4. Do we ask what is God? Let it suffice us to know that he is what he is, what he ever was, and ever will be. How little a portion is heard of him! Job 26:14.
That he is faithful and true to all his promises, unchangeable in his word as well as in his nature, and not a man that he should lie. Let Israel know this, I AM hath sent me unto you. - Matthew Henry