"Hear, O Israel: The LORD our God is one LORD" (Deuteronomy 6:4.) The original Hebrew is, "Shema Yisrael Adonai eloheinu Adonai echad."

(Above is the name of God in the original Hebrew. This is known as a tetragrammaton, YHWH.)

After man's rebellion in the garden of Eden, he began to worship false gods. The Israelites were the first people who were given and carried the knowledge of ONE, true God. They were fiercely monotheistic.

"What advantage then hath the Jew? or what profit is there of circumcision? Much every way: chiefly, because that unto them were committed the oracles of God" (Romans 3:1-2.)

'One' is translated from 'echad.' There can be no doubt as to its meaning in Deuteronomy 6:4. It declares ONE God without any distinction of 'persons' or co-existence of 'persons.' Yahweh is SINGLE, WHOLE, and an INDIVISIBLE Being (www.jewfaq.org/g-d.htm.)

Jesus quoted Deuteronomy 6:4 in Mark 12:29. "And Jesus answered him, The first of all the commandments is, 'Hear, O Israel, the Lord our God is one Lord'."

'LORD' is translated from the name of God, Yahweh (more frequenty translated Jehovah.) The name is so sacred to the orthodox Jew that he doesn't say it for fear of taking it in vain. This is why 'Adonai' is substituted for 'Yahweh' in Deuteronomy 6:4.

The declaration of one God is in the very first passage in the Shema (Hebrew for 'hear') and Jews place a greater amount of focus on Deuteronomy 6:4 than on any other passage of the shema.

YHWH (3068, Strong's concordance) is derived from the Hebrew root hayah which means 'to exist' or 'to become.' The name Yahweh can therefore be understood to mean eternal and self-existence.

God Himself declares His name to Moses in Exodus 3:14.

"And God said unto Moses, I AM THAT I AM: and he said, Thus shalt thou say unto the children of Israel, I AM hath sent me unto you."

'I AM' is translated from ehyeh which is derived from the Hebrew root word hayah. The name designates God's essential being - He exists and He is self-sufficient. 'Ehyeh' can be present or future tense. It could therefore be rendered "I will be what I will be".

Isaiah 57:15 says that Yahweh inhabits eternity. It is beyond the capability of the human mind to comprehend a Being who was never born or created but who simply exists. Yahweh is beyond time because not only is time finite, Yahweh created it.

It is contrary to the nature of Yahweh to cease to exist; this brings us to His self-existence. Yahweh is not dependent on anything to exist. How could He be? He created EVERYTHING seen and unseen including the heavens and the universe.

It is also contrary to the nature of God NOT to exist. GOD IS GOD because He Is, that is to say, because He exists.

Yahweh is infinite in His eternality; He has existed for an eternity of eternities before He created anything. Yahweh created time in order to encompass finite creation.

Genesis 1:1 not only records the creation of the heavens and the earth, it records the creation of time itself. Time is finite while Yahweh is infinite.

The Origin of the Name 'Jehovah'

The name Yahweh (YHWH) is so sacred to the Jew that it isn't verbally spoken for fear of unintentionally blaspheming it. The name Yahweh was replaced by the title 'adonai' in their sacred texts.

Hebrew is a consonantal language, i.e., it has no vowels. Vowels (to be more precise - vowel points) were added around the sixth century after Christ.

Whenever Jewish scholars encountered the name YHWH in their texts, the vowel points for 'adonai' were inserted underneath. This was a reminder to the people to not pronoun YHWH. While translitering the Bible into Latin, a sixteenth century German scribe combined the vowel points for 'adonai' into the Hebrew YHWH. The result was what we now know as Jehovah (JewFaq.com)

Jesus IS Yahweh

The Old Testament declares unmistakably that Jesus is Yahweh (Jehovah.) This is clearly seen in Numbers 13:16.

"These are the names of the men which Moses sent to spy out the land. And Moses called Oshea the son of Nun Jehoshua."

'Oshea' which means 'delivers, frees, saves' was Joshua's birth name. Moses changed it to Jehoshua (Strong's reference, 3091.) 'Jehoshua' is a combination of Yahweh and Oshea. Jehoshua literally means 'Yahweh saves or delivers!'

The name Joshua (Strong's reference, 3091,) as can be seen, is identical to the name Jehoshua.

(The Hebrew language, as is true for the Greek language also, has no 'j' sound. The correct transliterated spelling of Jehoshua is Yehoshua. The same is true for Joshua. It is correctly Yoshua or Yeshua. )

Joshua, Yoshua, Jeshua, or Yeshua, however you choose to say it, IS JESUS in English. Joshua who led the Israelites after the death of Moses is a type of Jesus the Messiah.

"Which also our fathers that came after brought in with Jesus into the possession of the Gentiles, whom God drave out before the face of our fathers, unto the days of David" (Acts 7:45.)

Stephen was giving a history of the Old Testament Jews to the members of the Jewish council (Acts 6:12.) 'Jesus' in Acts 7:45 is not the Son of God but the patriarch Joshua who succeeded Moses.

"Being made so much better than the angels, as he hath by inheritance obtained a more excellent name than they" (Hebrews 1:4.)

Jesus (the Son of God) inherited His name. He didn't inherit it from any angel because we are told that His name is more excellent than theirs. He also didn't inherit it from Joseph because Joseph wasn't His father. He therefore inherited His name from God the Father.

Jesus could not have inherited His name from God if the Father's name wasn't Jesus to begin with!

(Here is a natural illustration that will help. My name is Joseph Elijah Barrett. It was also my father's name. I received my name through inheritance from my father. Joseph Elijah Barrett was my father's name before it was my name.)

The Son born in Bethlehem of Judea HAD to receive His Father's name because He is God manifest IN THE FLESH. Of course this signifies that the name Jesus WAS God the Father's name BEFORE it was the Son's name.

"And she shalt bring forth a son, and thou shalt call his name JESUS: for he shall save his people from their sins" (Matthew 1:21.)

The Son had to receive His Father's name for identification. He is the ONE God Yahweh manifest in the flesh.

Yahweh declares emphatically that He is the ONLY Savior. "I, even I, am the LORD, and beside me there is no savior" (Isaiah 43:11.)

The Conversion of an Orthodox Jew

Then as now, the Jew is a staunch believer and follower of One God and One God only - Yahweh. They refuse to believe that Jesus is God.

Paul was a Pharisee who persecuted the Christians because he thought they were worshipping a false god. What could have possibly changed his mind concerning the identity of Jesus?

"And when we were all fallen to the earth, I heard a voice speaking unto me, and saying in the Hebrew tongue, Saul, Saul, why persecutest thou me? it is hard to kick against the pricks" (Hebrews 26:14.)

Prior to hearing this voice, Saul and his traveling companions saw a bright light emanating from heaven (Hebrews 26:13.)

The Pharisees in contrast to the Sadducees believed in angels and in the resurrection. They also retained the knowledge of the Hebrew language. Therefore it is safe to assume that Paul replied in Hebrew when he said, "...Who art thou, Lord?" (Hebrews 26:15a.)

The Hebrew word that Paul used could have been one of the following: Yahweh or Adonai. Paul knew his God as Yahweh, the God of the Old Testament. 'Adonai' is a title used only of Yahweh.

But it doesn't matter which word Paul used.

The voice that spoke to Paul identified himself as Jesus. The supernatural circumstances - the light which outshone the sun and the voice from the sky - convinced Paul beyond a shadow of a doubt that he was conversing with his God, Yahweh. He was therefore forced to confess that Jesus was Yahweh, the ONE, ONLY, and TRUE living God.

Yahweh is unchanging in His essence. He is ONE, WHOLE, and INDIVISIBLE. It is as impossible for God to suddenly become 'distinct persons' as it is for Satan to be saved. I could be even more emphatic by saying that it is more possible for Satan to become saved than it is for God to change His essence!

This Is Yahweh's Throne

"And immediately I was in the spirit and, behold, a throne was set in heaven, and one sat on the throne" (Revelation 4:2.)

John the apostle saw only one throne in heaven, and one Being sat on this throne. There is only one throne because there is ONLY ONE GOD! Jesus is that God. John saw Yahweh manifest in the flesh. This is Who every believer will see when raptured.
Sources: Judaism 101
Half Shekel
Jewish Virtual Library

One God

"Hear, O Israel: The LORD our God is one LORD" (Deuteronomy 6:4)

"And Jesus answered him, The first of all the commandments is, Hear, O Israel; The Lord our God is one Lord" (Mark 12:29)

"Thou believest that there is one God; thou doest well: the devils also believe, and tremble" (James 2:19)

"One God and Father of all, who is above all, and through all, and in you all" (Ephesians 4:6)

Jesus is God

"And Thomas answered and said unto him, My Lord and my God" (John 20:28)

"And we know that the Son of God is come, and hath given us an understanding, that we may know him that is true, and we are in him that is true, even in his Son Jesus Christ. This is the true God, and eternal Life" (I John 5:20)

Jesus is the Father

"I and my Father are one" (John 10:30)

"Then they said unto him, Where is thy Father? Jesus answered, Ye neither know me, nor my Father: if ye had known me, ye should have known my Father also" (John 8:19)

"But Jesus answered them, My Father worketh hitherto, and I work" (John 5:17)

"I am come in my Father's name, and ye receive me not: if another shall come in his own name, him ye will receive" (John 5:43)

"If ye had known me, ye should have known my Father also: and from henceforth ye know him, and have seen him. Philip saith unto him, Lord, shew us the Father, and it sufficeth us. Jesus saith unto him, Have I been so long time with you, and yet hast thou not known me, Philip? he that hath seen me hath seen the Father; and how sayest thou then, Shew us the Father?" (John 14:7-9)

"Being made so much better than the angels, as he hath by inheritance obtained a more excellent name than they" (Hebrews 1:4)

"And now I am no more in the world, but these are in the world, and I come to thee. Holy Father, keep them in thine name which thou hast given me that they may be one, as we are" (John 17:11, from the Majority Text)

Jesus is the Holy Ghost

"There is one body, and one Spirit, even as ye are called in one hope of your calling" (Ephesians 4:4)

"But the Comforter, which is thw Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your rememberance, whatsoever I have said unto you" (John 14:26)

"And I will pray the Father, and he shall give you another Comforter, that he may abide with you for ever; Even the Spirit of truth; whom the world cannot receive, because it seeth him not, neither knoweth him: but ye know him; for he dwelleth with you, and shall be in you. I will not leave you comfortless: I will come to you." (John 14:16-18)

"For I know that this shall turn to my salvation through your prayer, and the supply of the Spirit of Jesus Christ" (Philippians 1:19)

"Searching what, or what manner of time the Spirit of Christ which was in them did signify, when it testified beforehand the sufferings of Christ, and the glory that should follow" (I Peter 1:11)

Oneness of God > Jesus is Yahweh