The Shema reads:

Sh'ma Y'israel Adonai Eloheinu Adonai Echad:
Hear, O Israel: the Lord is our G-d, the Lord is One [echad].

The teaching of the Sh'ma sounds clear enough: G-d is One (i.e. He is not a trinity as most Pagan religions claim). This utterly simple declaration is confused by those seeking to usurp or surpass our Sacred Tradition. But the Sh'ma remains clear to those who are sincere: Adonai Echad.

The question (usually more of a challenge than a question) normally includes one of two points: It is argued that one might have single (echad) bunch of grapes, so maybe G-d is like that -- one, but really three. Or, since Adam and Chava (Eve) were "one (echad) flesh" then maybe G-d is like that, only three instead of two. Both are incorrect as we will see.

The Hebrew word echad means "one." Period. It is sometimes sadly humorous to see non-Hebrew speakers telling us what this simple word means: echad means "one" indivisible.

Echad can be modified, as in you and I may "be one" in our support for Jonathan Pollard's release etc, but in all such cases the word echad has been modified (as in 'of one accord', 'one bunch of grapes' etc.). If it is not modified echad means one and only one. The G-d of the Tanach is echad according to the Shema and scores of other direct statements: He is One, not three. It says echad in the Shema and it is not modified. Since the Shema was clearly revealed as the central declaration of our faith to proclaim the essential nature of the Holy One, in contrast to the beliefs of others (like the Ba'al worshippers whose gods are said to be one but manifested as different Baalim or masters/demigods), interpreting this word to mean more than one makes no sense contextually nor historically and indeed the very heart of biblical religion. The difference between the G-d of Israel and the gods of the nations is that HaShem is echad: utterly One. This is what monotheism means: One G-d.

In addition to what the word means, there is not a single verse in the Tanach that presents G-d as being more/other than echad (nor is His Oneness modified in any way). There is not a single verse in the Bible that presents the Ruach of HaShem (i.e. the Holy Spirit) as a third god nor as an individual being. It is the Presence HaShem not a separate being. Any conception other than strict monotheism is anti-Torah and denies the very heart Avraham's revelation, the teachings of Moshe Rabbeinu (i.e. the Torah), and the well established principles of Judaism and our sages throughout the ages.

Genesis 2:24 Therefore shall a man leave his father and his mother, and shall cleave unto his wife, and they shall be one flesh [hayah echad basar].

On this verse consider:

• Genesis 2:24 is talking about humans being in agreement, not about the nature of HaShem. One can not establish theology (an understanding of Theo-G-d) based on a comment made about human interactions.
• As humans Adam and Chavah (Eve) were equals who shared the 'breath of life' common to us all. No human is equal to nor independent of HaShem. While one can choose to submit to and thereby attain limited harmony with HaShem (as a tzaddik or righteous person), one can never become equal to Him in any sense. HaShem alone is Echad Elohim (the One G-d over all so-called gods).
• Genesis 2:24 modifies the word echad stating that 'they', plural, will become -- hayah -- i.e. they will "breath life together" -- AS THOUGH they were one flesh or person (echad basar). Adam and Chavah were not literally one flesh/person. They remained two distinct people with a common focus and identity. They were linked together as married individuals in their service to HaShem as though they were 'one person' sharing a common a breath.

Genesis 2:24 does not contradict the biblical teachings of the Shema and in fact has nothing to do with it.

Heretics believe several things that are not only not taught in the Bible, but that violate its clear teachings. While I have no interest in disparaging the beliefs of others, for those seeking biblical knowledge it is important to understand that the Trinity doctrine is but one example of misguided anti-biblical dogma. The G-d of the Bible is echad and there is no other god with Him. He alone is Utterly, Eternally, One within Himself and within all existence.

Exodus 34:14 For thou shalt bow down to no other god; for HaShem, whose Name is Jealous, is the Jealous G-d;

Deuteronomy 3:14 G-d said to Moses, "Ehyeh asher ehyeh (i.e. I [singular] will be what I {singular] will be)," and He said, "So shall you say to the children of Israel, 'Ehyeh (I [singular] will be) has sent me to you.'"

Isaiah 45:14: ...Surely G-d is in thee, and there is none else, there is no other god.

Everything other than the Holy One was birthed by another being. Ultimately all beings were created by HaShem alone. HaShem alone is echad as stated clearly in the Shema. HaShem owes His existence to none other. He alone exists complete unto Himself.

Deuteronomy 32:39 See now that it is I! I am the One, and there is no god like Me! I cause death and grant life. I strike, but I heal, and no one can rescue from My Hand!

HaShem takes this blasphemy very seriously:

Hoshea (Hosea) Chapter 13: When Ephraim spoke with trembling, he became exalted in Israel; when he became guilty through Baal, he died.
And now, they continue to sin, and they have made for themselves a molten image from their silver according to their pattern, deities, all of it the work of craftsmen; to them say, "Those who sacrifice man may kiss the calves."
Therefore, they shall be like a morning cloud, and like dew that passes away early, like chaff that is driven with the wind out of the threshing floor, and like smoke out of a chimney.
And I am the Lord your God from the land of Egypt, and gods besides Me you should not know, and there is no savior but Me.
I knew you in the desert, in a land of deprivation.
When they grazed and were sated, they were sated and their heart became haughty; therefore, they forgot Me...
You have destroyed yourself, O Israel, for [you have rebelled] against Me, against your help...

This could not be any more clear!

"I am the Lord your God from the land of Egypt,
and gods besides Me you should not know, and there is no savior but Me."

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