Elohim.
Is it ever plural in the OT? Seldom.
Is it ever singular in the OT? Almost always.
Is it ever plural in form in the OT? Always.
Is it ever plural in meaning when used in reference to YHWH? No. Never.
Is it ever singular when used in reference to YHWH? Yes. Always.
Is it the only Hebrew word that works this way? No. There are several Hebrew words that are always plural in form and either plural or singular in meaning. Dr. Menham Mansoor tells us in his popular textbook that they are known as dual number, and identifies six of them.
”2. Nouns with Plural Form Only
The following nouns are found in the plural form only. They are plural in form but may be singular or plural in meaning.”
(Menahem Mansoor, Biblical Hebrew, Vol. 1, p. 125)
The six are the Hebrew words for: God (elohim), mercy, life, face, water and sky / heaven.
Be careful when you hear someone say that elohim is plural. That’s misleading. What they should say is that it is “plural in form” -> which is true, but not necessarily the same as plural in meaning.
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All languages have their quirks. An English analogy.
“I saw the deer on my front lawn again last night.”
How many deer did I see?
One? (Singular.) From the statement, that’s possible; but incorrect.
Nine. (Plural.) That’s the number actually seen.
We can’t assume that deer is always singular or always plural in meaning.
”I saw the deer on my front lawn again last night. She ran when the beam from the headlights on my car shone upon her.” - singular
”I saw the deer on my front lawn again last night. They ran when the beam from the headlights on my car shone upon them. There were nine of them; all does.” - plural
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We can be absolutely certain that the elohim of Israel is singular. When the Israelites turned from him to any other elohim they were practicing idolatry.
Blessed be the God (Gk. theos, Heb. elohim; singular) of Israel -> a commendable expression of praise for the one and only true God.
Blessed be the gods (Gk. theoi, Heb. elohim; plural) of Israel -> a shameful expression of praise for idols.