Okay. The phrase "sons of God" can mean angels. You want to insist that it can carry no other meaning. The proof of such is a burden because the phrase is rarely used. Is that what Moses meant? Job used it to mean angels but did not use it to mean fallen angels. That doesn't help your case.
How many times was the exact phrase used in the Bible again? Do we have thousands of examples upon which to hang a doctrine or is the number less than that? Is the doctrine universally accepted or is it in dispute? And if there is dispute, shall I, your reader, have reason to give your opinion greater consideration than I do the opinion of others, by virtue of your having said it so earnestly?
Brother, there is a dispute about the entire bible. About if Jesus even died on the cross, yes? Were you there? Can you prove this for sure? Of course not, it is taken in faith and believed. That there were only a couple instances of scripture using the term sons of God as meaning angels, doesn't detract from it's validity. Is there an instance in scripture where it is used of man clearly? No. This would weaken your position in a way.SO what to do? Well we go to other scriptures which would support either view. This would seem to be the academically correct way to approach it it seems to me.
Are there other supporting scriptures that these beings in Genesis 6:4 were in fact something other than men? Perhaps. First I think we could agree that if "men of renown" were in fact fully human, that they would not bear children which were out of the norm for the type of children that men and women have when they bear children? I think this is a given.
So, let's see if there are any other scriptures which
may indicate that the "men of renown" were not merely nobles, or men of great wisdom. Let's see here...supposedly they Nephilim were giants, very large in size. I have heard it suggested that giants does not mean of large size, but rather nobles or men of great accomplishment. I have considered that with open mind, but over time keep finding scriptures which would indicate that they were in fact of great size. For instance:
Deuteronomy 9:1-3
Hear, O Israel: Thou art to pass over Jordan this day, to go in to possess nations greater and mightier than thyself, cities great and fenced up to heaven,
2 A people great and tall, the children of the Anakims, whom thou knowest, and of whom thou hast heard say, Who can stand before the children of Anak!
3 Understand therefore this day, that the Lord thy God is he which goeth over before thee; as a consuming fire he shall destroy them, and he shall bring them down before thy face: so shalt thou drive them out, and destroy them quickly, as the Lord hath said unto thee.(KJV)
A people great and tall. Hmm.
Numbers 13: 32-33
32 And they brought up an evil report of the land which they had searched unto the children of Israel, saying, The land, through which we have gone to search it, is a land that eateth up the inhabitants thereof; and all the people that we saw in it are men of a great stature.
33 And there we saw the giants, the sons of Anak, which come of the giants: and we were in our own sight as grasshoppers, and so we were in their sight./(KJV)
Of a great stature...we were in our own sight as grasshoppers, and so we were in their sight...
That doesn't seem to be describing nobles or men of great accomplishment brother. It would seem to be describing exactly what it says, men of great stature, very tall...giants. Now how in the world could regular men have children of such a great stature? It has been suggested before that we have so called men of great stature also. Men seven or eight feet tall. Ok, I understand this. But would they be of so great a stature so as to make regular men appear as grasshoppers? I think not. This seems to be talking about something else. So in my mind, these scriptures would seem to support JLB's theory of Fallen Angels making mischief with the women, and their children were the Nephilim and giants.
Ok, I have posted some other supporting scriptures which support the angel view (there are more, if you want them). I would ask at this time, if you have any supporting scriptures which would invalidate the angel view, or support your view? I am open minded, and will consider your scriptures carefully. It must be in scripture! The Lord would not lead us astray for He is not the author of confusion. I agree this is pretty twilight zoneish, but! the scriptures will indeed clear it up one way or the other. Will you my brother, consider these scriptures open mindedly, and consider the possibility of them meaning what they seem to indicate? If you think my interpretation is wrong, then I would politely ask for your alternate interpretation that would explain the confusion...
Have a blessed day in the Lord brother.