There were giants in the earth in those days; and also after that, when the sons of God came in unto the daughters of men, and they bare children to them, the same became mighty men which were of old, men of renown.While the other translations are also confusing here and there, there are a number of things that make the KJB sentence especially so.
Genesis 6, Verse 4
1. The placement of the semi-colon suggests that the biggest break is between the first clause and the rest of the sentence. But there really shouldn't be a break between it and "and also after that." Cf the oddity of: "There were giants in the earth in those days; and also after that."
2. What does the "when" clause modify: "those days", or "after that", or both? (The disruptive placement of the semi colon does not help in sorting this out)
3. Is "and they bare children to them" part of the when-clause? Semantically, this would make the most sense. But the immediately preceding comma, the overt subject ("they") and the change from present to past tense (from "came" to "bare"), make this interpretation more difficult. Cf:
"when the sons of God came in unto the daughters of men and bore children to them."
3. The tense change seems to serve no purpose other than to obfuscate.
4. What follows, as far as I can tell, is a comma splice. "the same became mighty men which were of old, men of renown" should either be its own sentence, or should be conjoined to what precedes it by "and."
5. Why "the same" instead of "they"?
6. An additional comma could reduce the additional obfuscation at the end: "which were, of old, men of renown"
This seems to me to be a classic case of iconicity in language: using linguistic form iconically to express or alter content. (onomopeia is another example). Here, the obfuscating punctuation, syntax, and morpho-syntax may serve to lend an aura of mystery to what might otherwise seem (to the writers of old? or the translators of new?) to be too straightforward for a religious text.
It would be interesting to see the original Hebrew, which, according to what little I've read, involves less embedding and more simple parataxis (sentences connected with "and"). That still leaves plenty of room for obfuscation.
Many other religious texts and/or translations, from what I know of them, rely heavily on an obfuscation that is partially linguistic (Zen koans?)
I've suspected the same thing of certain philosophers (Kant, Hegel) and a number of postmodernists as well.
My preference is for maximum linguistic clarity: the best messages, however mysterious, should shine rather than fade away when viewed in the light of a well-written sentence.