Thank you for the biblical question on Job 1:6, “Is job 1:6 biblical proof that the sons of God were of an angelic nature and not of the line of Seth as thought in Genesis 6:4?”
When one does a critical study, it is best to rely on the Hebrew and or Greek text rather than a translation of the Greek text.
The NIV translates Job 1:6 as this, “One day the angels came present themselves before the LORD, AND Satan also came with them.”
John Owens, Analytical Key to the Old Testament translates Job 1:6 as this, “Now there was a day when came the sons of God to present themselves before YAHWEH and came Satan also among them.”
As one reads the context, here are some observations including some assumptions on my part:
1. Before the writing of Job, Satan had already rebelled against God.
The name Satan means Accuser. Satan is the one who makes accusations against the followers of God. If that name is assigned to him, it means that he had already rebelled against God.
2. The “sons of God” are angelic beings.
The text cites that the sons of God presented or came before YAHWEH (LORD). There is no indication within the text that the sons of God are human beings. The place where the sons of God came before God is in heaven, not on earth. Thus, the sons of God have been interpreted to being angelic beings that didn’t follow Satan.
Satan comes among the angelic beings. It is Satan who accuses Job of worshiping and obeying God because of his blessing from God. None of the other angels in the presence of God make that accusation about Job. It is only Satan.
3. The citation of Job 1:6 only affirms angelic beings and Satan.
One may make a conclusion that the sons of God are not likely half angelic beings and half human. It is debated whether the fallen angels had sexual relationship with females who birth partial angelic and human beings.
It can be concluded that the half angelic and half humans, if one accepts that interpretations, are unable to come into the presence of God. Flesh and blood can’t physically come into the presence of God. God comes to man, not that man comes into the very presence of God.
Summary: One must look at the other passages that refers to the “sons of God” and its interpretation in the context. It would be faulty to base one’s theological or biblical belief on one verse.
-Kingston