e three names for God in the Old Testament.

First El, or Elohim, the Mighty One: by which, so Moses says, God
was known to the Jews before his time, and which sets forth God's
power and majesty--the first thing of which men would think in
thinking of God.

Next Jehovah. The I Am, the Eternal, and Self-existent Being, by
which name God revealed himself to Moses in the burning bush--a
deeper and wider name than the former.

And lastly, Adonai, the Lord, the living Ruler and Master of the
world and men, by which he revealed himself to the later Jews, and
at last to all mankind in the person of our Lord Jesus Christ.

Now I need not to trouble your mind or my own with arguments as to
how these three different names got into the Bible.

That is a matter of criticism, of scholarship, with which you have
nothing to do: and you may thank God that you have not, in such
days as these. Your business is, not how the names got there, which
is a matter of criticism, but why they have been left there by the
providence of God, which is a matter of simple religion; and you may
thank God, I say again, that it is so. For scholarship is Martha's
part, which must be done, and yet which cumbers a man with much
serving: but simple heart religion is the better part which Mary
chose; and of which the Lord has said, that it shall not be taken
from her, nor from those who, like her, sit humbly at the feet of
the Lord, and hear his voice, without troubling their souls with
questions of words, and endless genealogies, which eat out the
hearts of men.

Therefore all I shall say about the matter is that the first chapter
of Genesis, and the first three verses of the second, may be the
writing of a prophet older than Moses, because they call God Elohim,
which was his name before Moses' time; and that Moses may have used
them, and worked them into a book of Genesis; while he, in the part
which he wrote himself, called God at first by the name Jehovah
Elohim, The Lord God, in order to show that Jehovah and El were the
same God, and not two different ones; and after he had made the Jews
understand that, went on to call God simply Jehovah, and to use the
two names, as they are used through the rest of the Old Testament,
interchangeably: as we say sometimes God, sometimes the Lord,
sometimes the Deity, and so forth; meaning of course always the same
Being.

That, I think, is the probable and simple account which tallies most
exactly with