Well, it's still possible to make a vain promise, though we no longer have the habit of making the oath by way of God's name, save for the occasional "I swear to God!" It's clearly a commandment about not diluting The credibility of God's name, and clearly had more force in a culture that had a hard time enforcing written contracts: someplace with the economy would have largely relied on person-to-person credit, as you sometimes see in very impoverished communities today.

In that context, keeping sacred certain ways of making promises makes a great deal of utilitarian sense. If people keep to the third commandment, then you know that somebody who swears by God is either reliable or taking the risk of blasphemy and punishment on his head. I suspect he also took the risk of literal punishment by the religious Courts though I'm not sure about the history on that.

Last edited by iwpoe (4/24/2016 1:47 am)

They still follow this interpretation when they read the MT. The words of "YHWH" are given the vocalization of "Adonai" in homage to the third commandment. However, the context of the Decalogue, both when Moses gave them from Mt. Sinai and in first-century Judaea when there was still a temple, the intended interpretation had to do with sacrifices.

Of course, there is some overlap to how we use God's name in speech, as back then nobody would mention God unless they were going to either expound theology or make an oath.

RE: Jacob, the meaning of any word is determined by context. The whole reason Jacob is making the comparison between his brother's face and "the face of God" is because the latter has connotations of extreme graciousness, and this simile would be lost if "elohim" meant just a generic judge or prince.

Tomislav Ostojich wrote:

They still follow this interpretation when they read the MT. The words of "YHWH" are given the vocalization of "Adonai" in homage to the third commandment. However, the context of the Decalogue, both when Moses gave them from Mt. Sinai and in first-century Judaea when there was still a temple, the intended interpretation had to do with sacrifices.

I'm truly curious as to how you arrived at that conclusion, save for the fact that the New Testament only mentions it with reference to the Temple and sacrifices. I ask this because as a Talmudist it is quite clear to me that the traditional interpretation goes back to well before Jesus's time.

RE: Jacob, the meaning of any word is determined by context. The whole reason Jacob is making the comparison between his brother's face and "the face of God" is because the latter has connotations of extreme graciousness, and this simile would be lost if "elohim" meant just a generic judge or prince.

First of all, I always understood the text to mean that Jacob was telling Esau (who, as you will recall, was liege to 400 men) that his visage is as noble as a lord, thus mollifying him with regards to the lost blessing.

Second, even on your own account, Jacob was not invoking God Himself, but was rather referring to Esau as 'Godly'. How are you comparing that to invoking God in vain?
 

The English is:

You shall not take the name of the LORD your God in vain, for the LORD will not leave him unpunished who takes His name in vain.

And the Hebrew:

לֹ֥א תִשָּׂ֛א אֶת־שֵֽׁם־יְהוָ֥ה אֱלֹהֶ֖יךָ לַשָּׁ֑וְא כִּ֣י לֹ֤א יְנַקֶּה֙ יְהוָ֔ה אֵ֛ת אֲשֶׁר־יִשָּׂ֥א אֶת־שְׁמֹ֖ו לַשָּֽׁוְא׃ פ

The word 'take' is תִשָּׂ֛א "to lift, carry, bear, take, take away" 

The words 'in vain' are לַשָּׁ֑וְא "emptiness, vanity; emptiness of speech, lying"

Jason is quite right that an important aspect could certainly be taking/bearing God's name when one is oneself false. I think Christ thinks about it that way (as usual, he gives a psychologizing interpretation): he thinks that the point is that your own word should be good enough that you don't need to be swearing by God all the time.