YHVH: This name was uniquely related to God's covenant with Israel. It was His covenant name.(1)YHVH contains the aspects of past, present, and future.
This name of God cannot be pronounced because it has no vowels, although some Hebrew Bibles insert vowels so that it can be pronounced YAHWEH or J(Y)EHOVAH. The correct pronunciation has been lost over time so most Jews do not pronounce it at all, out of fear, concern and respect of accidentally using God's name in vain. It is common practice to use the substitute word "Adonai." Out of respect for the name of the Lord, sometimes Jewish authors do not even write the YHVH name in full, either as YHVH or Adonai. Instead, they just write two "Yodh" characters. Out of the same concern for using God's name in vain, often in english, God is often represented as G-d.
Both YHVH and Adonai mean "Lord", and this is how it is translated in most Bibles. It is often written in capital letters "LORD" so it can be distinguished from all the other names of God. Adonai is the plural of "Adon" which means a temporal lord, or a person in authority, just as "Elohim" is the plural of "Elah." This does not imply that there is more than one Lord, or more than one God. There is one Lord God with multiple natures or personalities.
Same vowels were added to both words. (Because it was considered too holy to utter, down through the ages YHVH was vowel pointed with the vowels for Adonai).(2) The Tetragrammaton (YHVH) was pronounced 10 times during the twenty-four hour holiday (Day of Atonement). Three of those ten came during the Confessional Prayer Of The High Priest. The appropriate response when heard by the congregation was "Blessed be His name, the glory of His kingdom is forever and ever. This is after they fell with their faces to the ground.(3)
In the Isaiah 43:11 prophecy God tells us that the LORD (YHVH) is also the saviour which teaches the divinity of our Messiah. For more on this prophecy please view Isaiah 43:11.
I, even I, am the LORD, and apart from me there is no savior. (Isaiah 43:11).
The prophet Jeremiah may provide yet another clue when he elaborates on the designation of the Messiah as the Branch that grows from Jesse's roots (23:5-6).
He says one of the Messiah's names is "The LORD 
Our Righteousness." This is in effect equating the name of the Messiah with God.
When the Messiah comes we may learn the correct way to pronounce this name of God.
One interpretation of the names meaning is "The One who exists."
This one of God's names brings with it the idea of mercy.
There is a Kabbalistic view that each of the Four Species used during the Feast Of Tabernacles is associated with the four letter name of God.
Jehovah is different from the other two primary names, Elohim and Adonai. Jehovah is personal. It can apply to only one deity-the God of the Hebrew people, the descendants of Abraham, Isaac, and Jacob.(2)
One possible explanation for the composition of the name Jehovah from the Hebrew might be yehi-he will be; hovi-being; hah yah-he was. Jehovah might also be understood as an acronym using parts of the same Hebrew words, making Yehov-ah, a name that sates, "I will be (future) because I am (present) because I was (past)."(2)
The Jewish Tetragrammaton YHVH- the sacred name of God- in fact derived from Jehovah, an androgynous physical union between the masculine Jah and the pre-Hebraic name for Eve-Havav.(4)Please see these related pages concerning the YHVH name.
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1). The MacArthur New Testament Commentary on the book of Hebrews p.175.
2). Israel My Glory, (A Friends of Israel publication) Thomas Simcox, July Aug, 2003
3). The Fall Feast of Israel (Yoma 3:8). (Mitch and Zhava Glaser).
4). The Da Vinci Code by Dan Brown p.309
