The Hebrew ben and Aramaic bar, “son,” designate not only a male descendant but also a relationship to a community, a country, a species (e.g., animals), etc. “Son of God” can thus mean both a mythological figure of divine origin, a being belonging to the divine sphere (such as an angel), or a human being having a special relationship to a god. In antiquity, son of god was used predicatively of kings begotten by a god (in Egypt) or endowed with divine power (in Mesopotamia). In the Roman period, it also was used in the East as a title for the emperor.

In the Hebrew Bible, sons of God occur in Genesis 6.1–4, where they marry human women and became fathers of the giants (KJV) or Nephilim (NRSV); in Job 1.6; 2.1 (NRSV: “heavenly beings”), where they make up the court of God; and also in Deuteronomy 32.8 (NRSV: “gods”); Psalms 29.1 and 89.6 (NRSV: “heavenly beings”); cf. Psalm 82.6 “sons of the Most High” (NRSV: “children of the Most High”). Elsewhere, the designation son of God is used especially of the king. Thus, in the primary passage of the Israelite ideology of divine kingship, it is said of Solomon, “I will be his father, and he will be my son” (2 Sam. 7.14; cf. 1 Chron. 17.13). Neither in 2 Samuel 7.12–14 nor in Psalm 89.26–29 does the designation son of God express anything more than a special relationship; there is no question of deification. This also applies to Psalm 2.7, where God says to the king, “You are my son; today I have begotten you”; “today” rules out a mythological interpretation. The title son of God indicates that the king has his kingdom from God, and the saying belongs to the coronation day or its anniversary. (See also Kingship and Monarchy; Messiah.)

This manner of speaking of God as a father and the correlative usage, son or sons of God, has also been extended to cover the people of God. In Exodus 4.22 and Jeremiah 31.9, God calls Israel his firstborn son; in Exodus 4.23 and Hosea 11.1 his “son.” Correspondingly, in Deuteronomy 32.6, 18 and Jeremiah 3.4, God is called the people's “father,” and in Deuteronomy 14.1; 32.5, 19 the Israelites appear as “sons” (and “daughters”) of God. Finally, the plural form may designate a special group, like the pious (Ps. 73.15) or the priests (Mal. 1.6).

In postbiblical literature, “son of God” designates either the pious (Sir. 4.10) or the suffering righteous (Wisd. of Sol. 2.18; cf. 2.13, 16; 5.5; cf. also Psalms of Solomon 13.9), while the plural denotes the elect people (Wisd. of Sol. 9.7; 12.19, 21; Psalms of Solomon 17.27). Obviously, son of God was not a common messianic title in Judaism before Roman times. Passages like 2 Esd. 7.28–29; 13.32, 37, 52; 14.9, which speak of “my son [the Messiah],” and 1 Enoch 105.2, do not alter this, since both are influenced by the “servant of the Lord” in Second Isaiah. Messianic usage of the expression outside the New Testament from this period does occur in the Dead Sea Scrolls, as in a fragment of a Daniel Apocryphon from Qumran (4QpsDan Aa) and in 4Q246, another fragment, which has a close parallel in Luke 1.32, 35. But the fact that the title was used for the king makes it understandable that it could also be applied to the Messiah.

In the New Testament, Son of God (and its abbreviated form, “the Son”) is a title often used in christological confessions. From the beginning it seems to have been used in connection with the belief in the resurrection and exaltation of Jesus. The confessional fragment in Romans 1.3–4 speaks of the gospel “concerning his Son, who was descended from David according to the flesh and was declared to be Son of God with power according to the spirit of holiness by resurrection from the dead.” The originally exchangeable expressions Son of David and Son of God are here conferred on the earthly Jesus and the risen Lord, it being presupposed that before his death Jesus was Messiah‐designate, and that the resurrection implied a new position (cf. Acts 2.36). The authors of Acts 13.33 and Hebrews 1.5; 5.5 also quote Psalm 2.7 in this connection. Yet it is still possible to speak of a special “Son of God” Christology insofar as the designation expresses Jesus' unique relationship to God. From an early stage, this belief included the idea of a preexistence and the sending of Jesus to the world (cf. Gal. 4.4 and also Phil. 2.6–11; John 1.1). The title seems to have attracted to it ideas connected with wisdom as well.

In the synoptic Gospels we may observe how the title Son of God has penetrated into the traditions about the life of Jesus. In Mark, it is used only by God and the demons (cf. 1.11; 9.7; 3.11; 5.7); the one time it is used by a human (15.39), the past tense (“was”) suggests a distinction between the confession of the centurion to the deceased Jesus, and later on, to the risen Lord. In Matthew we also find it in the confessions of the disciples (14.33; 16.16; cf. also 26.63), in the story of the temptation (4.3, 6), and the story of the mocking at the cross (27.43; cf. also Matt. 11.27). In Luke, it is mostly found in traditional material; the idea of a virgin birth probably does not belong here. In John, the Son of God, together with the title the Son, plays a central role in depicting Jesus as being one with the Father (e.g., 3.35–36 and 1.18; 10.30).

The origin of the title seems, in the first place, to be Jesus' unique addressing God as father (see especially Mark 14.36, where the Aramaic abba is preserved), and second, its connection with kingship ideology in view of the conviction that Jesus was the anticipated son of David. Yet characteristically in the New Testament it stands beside the usage of the phrase sons of God, referring to those whom Jesus has brought to salvation (Rom. 8.14–21; 9.8, 26; Gal. 3.26; Matt. 5.9, 45; John 1.12; 1 John 3.1). In the apostolic fathers, the designation describes the divine nature of Jesus as apart from his human nature (e.g., Ignatius, Ephesians 20.2; Epistle of Barnabas 12.10, where it corresponds to son of man).

To summarize the evidence in the New Testament, it might be said that the title Son of God primarily expresses Jesus' unique relation to God, while the Lord, the christological title preferred by Paul (see 1 Cor. 12.3; Phil. 2.11), emphasizes his position in the church and in the world.

Mogens Müller