The Son of God/Son of David and The Good News
When it comes to whether or not Jesus is the Messiah, there is no disagreement between Christians and Jewish people that the Messiah has to be a descendant of David. The area of disagreement is when Christians assert that Jesus is the divine Son of God. What Christians tend to forget is that the designation “Son of God” is used in various ways in the Old Testament—not just to refer to God’s only begotten Son in the way Christians would assume. When Jewish people thought of the Davidic King as the Son of God, it had very little to do with the Second person of the Trinity. In other words, “Son of God” didn’t denote divinity. Even though divine sonship does appear in the Jewish Scriptures in reference to persons or people groups, such as angels (Gen. 6:2; Job 1:6; Dan. 3:25) and Israel (Exod. 4:22-23; Hos. 11:1; Mal. 2:10), the category that has special importance to the Son of God issue is that of king.
Not only did God promise that Israel would have an earthly king, (Gen. 17:6; 49:6; Deut. 17:14-15), he also promised David that one of his descendants would rule on his throne forever ( 2 Sam. 7:12-17; 1 Chron. 17:7-15). In other words, David’s line would eventually reach its climax in the birth of a person who would guarantee David’s dynasty and throne forever. For example, Psalm 2 (which is a coronation hymn, similar to 2 Kings 11:12) describes the king’s crowning. Just as 1 Chronicles informs us that “the fame of David went out into all lands; and the LORD brought the fear of him upon all nations,”  so God tells the person to whom he is speaking that He is turning over the dominion and the authority of the entire world to Him (v. 8). In addition, Psalm 2 declares that God will ultimately subjugate all nations to the rule of the Davidic throne. In Psalm 89:24-27, the Davidic King is elevated over the rivers and seas and is the most exalted ruler on earth. He also will be the “firstborn” and enjoy the highest rank among all earthly kings. In Psalm 110, the Davidic King is invited to sit at God’s “right hand,” and is called “lord” and called a “priest” after the pattern of Melchizedek. John Collins, who is a specialist on this topic, says the following about the Davidic Messiah:
This concept of the Davidic Messiah, as the warrior king who would destroy the enemies of Israel and institute an era of unending peace constitutes the common core of Jewish messianism around the turn of the era. . . . There was a dominant notion of a Davidic Messiah, as the king who would restore the kingdom of Israel, which was part of the common Judaism around the turn of the era.
Collins goes on to say:
He is the scepter who will smite the nation, slay the wicked with the breath of his lips and restore the Davidic dynasty. Hence his role is in the eschatological war. He is the Messiah of righteousness, who will usher in an era of peace and justice. He is presumably a human figure, although he is endowed with the Spirit of the Lord. He is expected to restore a dynasty rather than rule himself.
There is also a text in the Qumran literature, which predates the New Testament, about the Davidic King:
[And] Yahweh [de]clares to thee that he will build thee a house; and I will raise up thy seed after thee, and I will establish his royal throne [forev]er. I wi[ll be] a father to him and he shall be my son. (2 Sam.7.11c, 12b-c, 13, 14a). This is the Branch of David which will arise with the Seeker of the law and who will sit on the throne of Zion at the end of days; as it is written I will raise up the tabernacle of David which is fallen [Amos 9.11]. This tabernacle of David which is fallen (is) he who will arise to save Israel. (4Qflor.1.110-13) 
Furthermore, though Luke calls Yeshua the “Son of the Most High,” there is a similar theme in Qumran literature:
He will be called the son of God, and they will shall call him the son of the Most High. . . . until the people of God arises and makes everyone rest from the sword. His kingdom will be an eternal kingdom, and all his paths truth. He will judge the earth in truth and all will make peace. The sword will cease from the earth and all the provinces will pay him homage. The great God is his strength, he will wage war for him; he will place the peoples in his hand and cast them away before him. His rule will be an eternal rule (4Q246 II, I, 1-9).
Collins goes on to concede that even if the dominant Messianic expectation mostly revolved around a Davidic warrior, hardly anything in the Gospels corresponds with the Jewish expectation of a militant messiah. Keeping these principles in mind, let’s look at Romans 1:1-5:
Paul, a bond-servant of Christ Jesus, called as an apostle, set apart for the gospel of God, which He promised beforehand through His prophets in the holy Scriptures, concerning His Son, who was born of a descendant of David according to the flesh, who was declared the Son of God with power by the resurrection from the dead, according to the Spirit of holiness, Jesus Christ our Lord, through whom we have received grace and apostleship to bring about the obedience of faith among all the Gentiles for His name’s sake, among whom you also are the called of Jesus Christ; to all who are beloved of God in Rome, called as saints: Grace to you and peace from God our Father and the Lord Jesus Christ.
Here we see Paul’s message of Good News is the following: Yeshua is the Son of God/The Davidic King (2 Sam 7:14; Ps 2:2, 7; 89:19-21, 26-27) and there will always be a King on the throne of David. Thus, Jesus is “designated” or “declared” as the Son of God and this “Good News” was announced in the Jewish Scriptures. As seen in 2 Samuel 7:12-17, the immediate prophecy is partially fulfilled in David’s son Solomon. However, as already said, the word “forever” shows there are future descendants to come. God promised David that his “seed” would establish the kingdom. There were two possibilities for a coming Davidic King to rule forever: Either God could continually raise up a new heir, or He could have someone come who would never die. Better yet, He had someone come who did die, but who rose again to live forever. Does this sound like the need for a resurrection?
So now a pertinent question arises: “How many modern day Gospel presentations utilize what Paul says here in Romans 1:1-5 about the Davidic King?”
 H. W. Bateman IV, D. L. Bock, and G. H. Johnston, Jesus the Messiah: Tracing the Promises, Expectations, and Coming of Israel’s King (Grand Rapids: Kregel Academic, 2012), 80.
 Ibid, 97.
[4)J. J. Collins, The Scepter and the Star: The Messiah of the Dead Sea Scrolls and Other Ancient Literature (New Haven, Connecticut: Yale University Press, 2007), 68, 209.
 C. A. Evans, Jesus and His Contemporaries: Comparative Studies (Leiden: Brill. 2001), 104.
A. M. Mengestu, God as Father in Paul: Kinship Language and Identity Formation in Early Christianity (Eugene, OR: Pickwick Publications, 2013), 154.