What’s special about Exodus 6:3, Psalms 83:18, Isaiah 12:2, & Isaiah 26:4? Why does the Authorized Version translate the Tetragrammaton as Jehovah in those four verses, but replace it with LORD or GOD everywhere else?
The general policy of the writers of the Authorized Version was that the divine name, also called the Tetragrammaton (usually rendered "YHWH" or "Yahweh" today but often "Jehovah" in older times), would not be rendered directly, but would be replaced with "the LORD".
There are a number of exceptions to this. These exceptions are:
- When the Tetragrammaton is specifically referred to as the name of God. This is the case in Exodus 6 and Psalm 83. Writing things like "my name is the LORD" would make little sense.
- When the divine name is used as part of a place name, such as "Yahweh Yireh" (or "Jehovah-jireh"). Again replacing the name with "the LORD" makes no sense in these circumstances. These cases are not listed in the question.
- When the name is repeated by combining it with a derivative or alternate version of itself. Again "the LORD LORD" does not make sense (although other translations render it "the Lord, the Lord himself"). This is the case in Isaiah 12 and 26.
It is unarguable that the ancient Hebrew text of what we now call "The Old Testament" had the divine name written 6,961 times. Those four Hebrew letters spell YHWH, often rendered as Yahweh. This is the Tetragram and, in some translations is transliterated as Jehovah. Yes, the Authorised (King James) Version has it in the four places stated in the question.
However, it should be pointed out that it has it in three other places, as follows:
"And Abraham called the name of that place Jehovah Jireh" [Jehovah will provide]. Genesis 22:14
"And Moses built an altar, and called the name of it Jehovah Nisi" [Jehovah is my banner]. Exodus 17:15
"Then Gideon built an altar there unto the LORD, and called it Jehovah Shalom" [Jehovah is peace]. Judges 6:24
The first instance referred to a place in Jerusalem, afterwards called Moriah. The second instance was circa. B.C. 1491 to commemorate the defeat of the Amalekites. The third instance was after a miraculous communication from God to Gideon, circa. B.C. 1256
So, there are seven instances. Of course, that is still woefully short of the total of 6,961 times where the Tetragram was originally written! This seems to be an instance of inconsistency in the Authorised Version. There would be nothing wrong with transliterating it as either Yahweh or Jehovah all 6,961 times, to be consistent. Young's Literal Translation (1898) does that, as Jehovah.
I looked through what articles and literature I have of the Trinitarian Bible Society, but could not find one on their use of the Tetragram. I also looked at their web-site but could not find any way of tracking down that specific point. Really, the best way of getting an answer would be for you to contact them and ask them directly about this inconsistency. Their web-site is http://www.tbsbibles.org