For over two hundred years' people did not call on God by name. It wasn't until the birth of Adams grandson Eno's, that men began to call upon the name of the Lord.
God explained to Moses that He had appeared to Abraham, Isaac, and Jacob. Moses was given the task of returning to Egypt and demanding the release of the Israelite slaves.
Moses asked God When I come unto the children of Israel and shall say unto them, the God of your fathers hath sent me unto thee, and they say to me, what is his name? What shall I say unto them. God said to Moses "I AM THAT I AM" and He said, thus you shall say to the sons of Israel, I AM has sent me to you." God goes on to say to Moses... "Thus, you shall say to the sons of Israel, The LORD, the God of your fathers, the God of Abraham, the God of Isaac, and the God of Jacob, has sent me to you. This is My Name forever, and this is My Memorial-Name to all generations."
Holy; Creator; The Most-High God; Righteous; Joy; Peace; Lord Mighty in Battle; God of the Battle; Conquer; High Tower and Strong Tower; Defender; Deliver; Thy Strength; Thy Sword; Thy Shield; Your Rock; The Wine; Your Fortress; Your Refuge; Shepherd; Kingsman Redeemer; Jubilee; Horn of thy Salvation; Sanctifier; Love; Mercy; Grace; Hope; Provider; Healer; Omnipresent; Omnipotent; Judge and Jealous.
Now there are covenant names of Jehovah and redemptive names through which God revealed himself to Israel. These different names do not signify 40 different God's, but HIS Characteristics, or HIS attributes.