Jews, Christians and Muslims all believe in one God (monotheism) and the founders are all descendants of Abraham. But, they call God by different names, Elohim (אֱלהִים) (Hebrew), ehyeh (Ancient Hebrew), Yahweh (YHWH*) (Modern Hebrew), Elaha (Aramaic), Jehovah (anglicized version of YHWH), Allah (Al-Lah) (Arabic) or God.
You have to look at a Hebrew version of the bible to see these.
Yahweh or Jehovah (Lord, Master) is used 6,519 times. Yahweh is first used in Gen 2:4.
Jehovah does appear in the King James Version in [Exodus 6:3]
Elohim (God, Judge, Creator) is used over 2,000 times. It is first used in Gen 1:1.
El Shaddai (All-Sufficient One, Lord God Almighty) (17 times) First used in Gen 17:1.
Adonai (Lord, Master) (434 times) elappears in Isaiah, Ezekiel and Daniel.

. * The letters יְהוָה YHWH/YHVH [Exodus 6:3] are referred to as the Hebrew Tetragrammaton (a grammatical substitution of a word or letters/symbols from another language) representing the name of God.
The ancient pronunciation is not known. Josephus, who as a first century priest and historian knew the pronunciation of the name, declares that religion forbids him to divulge it.

The new Jewish Publication Society Tanakh 1985 follows the traditional convention of translating the Divine Name as "the LORD" (in all caps).
When the Divine Name is read during prayer, "Adonai" ("My Lord") is substituted.
More Recent Christian Bibles (NIV, NRSV, ..) use "LORD" also.

Exodus 3:14-15, where God gives his name as אֶהְיֶה אֲשֶׁר אֶהְיֶה, translated most basically as "I am that I am" (or "I will be that which I now am"), could theoretically be a hif'il verb inflection of root HWH, with a meaning something like "he who causes to exist" or "who gives life".

One explanation for multiple names for God in the old testament is the JEPD theory of multiple authors of the first five books of the old testament (The Torah)

Christian fundamentalists will point to some different concepts of God in the Bible and Quran to show he/she is a different God.

According to "A History of God: The 4,000-Year Quest of Judaism, Christianity and Islam" (1993) by Karen Armstrong, "Muhammad thought that al_Lah was identical to the Jews and Christians God." and "They have developed remarkable similar ideas of God."
See God on the Islam page
Christians view God as three persons (the trinity), Father, Son (Christ) & Holy Spirit; See Deity of Christ.

Christ's Name:
"Wonderful, Counselor, Mighty God, Everlasting Father, Prince of Peace."~Isaiah 9:6
You will conceive and give birth to a son, and you are to call him Jesus. Luke 1:31
Today in the town of David a Savior has been born to you; he is the Messiah, the Lord. Luke 2:11

the Jewish tradition of not speaking God's Name
JEPD theory of multiple authors
The Names of God in the Old Testament at
God on the Islam page

last updated 15 Dec 2011