What is the definition of son of God in Job 2:1?
For the Chosen People, it usually refers to the Hebrew nation or people in general.
Although references to "sons of God", "son of God" and "son of the LORD" are occasionally found in Jewish literature, they never refer to physical descent from God. There are two instances where Jewish kings are figuratively referred to as a god. The king is likened to the supreme king God. These terms are often used in the general sense in which the Jewish people were referred to as "children of the LORD your God".
When used by the rabbis, the term referred to Israel or to human beings in general, and not as a reference to the Jewish mashiach. In Judaism the term mashiach has a broader meaning and usage and can refer to a wide range of people and objects, not necessarily related to the Jewish eschaton. - Son of God
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Sons of the God (Hebrew: בני האלהים) literally: "sons of the Gods") is a phrase used in the Hebrew Bible and apocrypha. The phrase is also used in Kabbalah where bene elohim are part of different Jewish angelic hierarchies.
And it came to pass, when men began to multiply on the face of the earth, and daughters were born unto them, That the sons of God saw the daughters of men that they were fair; and they took them wives of all which they chose. And the LORD said, My spirit shall not always strive with man, for that he also is flesh: yet his days shall be an hundred and twenty years. 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. — Genesis 6:1–4, KJV
The first mention of "sons of God" in the Hebrew Bible occurs at Genesis 6:1–4. In terms of literary-historical origin, this phrase is typically associated with the Jahwist tradition.3
This passage has had two interpretations in Judaism:
Offspring of Seth: The first references to the offspring of Seth rebelling from God and mingling with the daughters of Cain are found in Christian and rabbinic literature from the second century CE onwards e.g. Rabbi Shimon bar Yochai, Augustine of Hippo, Julius Africanus, and the Letters attributed to St. Clement. It is also the view expressed in the modern canonical Amharic Ethiopian Orthodox Bible. In Judaism "Sons of God" usually refers to the righteous, i.e. the children of Seth.
Angels: All of the earliest sources interpret the "sons of God" as angels. From the third century BCE onwards, are references are found in the Enochic literature, the Dead Sea Scrolls the (Genesis Apocryphon, the Damascus Document, 4Q180), Jubilees, the Testament of Reuben, 2 Baruch, Josephus, and the book of Jude (compare with 2 Peter 2). This is also the meaning of the only two identical occurrences of bene ha elohim in the Hebrew Bible (Job 1:6 and 2:1), and of the most closely related expressions (refer to the list above). In the Septuagint, the interpretive reading "angels" is found in Codex Alexandrinus, one of four main witnesses to the Greek text.
Rabbinic Judaism traditionally adheres to the first interpretation, with some exceptions, and modern Jewish translations may translate bnei elohim as "sons of rulers" rather than "sons of God". Regardless, the second interpretation (sons of angels or other divine beings) is nonexistent in modern Judaism. This is reflected by the rejection of Enoch and other Apocrypha supporting the second interpretation from the Hebrew Bible Canon.
Using Scripture to interpret Scripture is a very common practice in our day and as such the New Testament in the person of St. Luke shows us that the Sons of God were the descendants of Adam.
According to Scripture “sons of God” means “persons who are begotten independently of any creature’s decision”. All angels can appropriately be called “sons of God”, but not all characters called “sons of God” in the Bible can appropriately be considered angels. The “sons of God” in Genesis 6:1-4 are undoubtedly human, and it is fitting to consider that they were created directly by God through transformation of human-like animals into persons.
Who was the son of Enos, who was the son of Seth, who was the son of Adam, who was the son of God. - Luke 3:38