You need to read the rest of the Bible, esp. the NT epistles written by Jesus' disciples. They have a different perspective.
"Men of Israel, hear these words: Jesus of Nazareth, a Man attested by God to you by miracles, wonders, and signs which God did through Him in your midst, as you yourselves also know-- Him, being delivered by the determined purpose and foreknowledge of God, you have taken by lawless hands, have crucified, and put to death; whom God raised up, having loosed the pains of death, because it was not possible that He should be held by it. For David says concerning Him: 'I foresaw the Lord always before my face, For He is at my right hand, that I may not be shaken. Therefore my heart rejoiced, and my tongue was glad; Moreover my flesh also will rest in hope. For You will not leave my soul in Hades, Nor will You allow Your Holy One to see corruption. You have made known to me the ways of life; You will make me full of joy in Your presence.' "Men and brethren, let me speak freely to you of the patriarch David, that he is both dead and buried, and his tomb is with us to this day. Therefore, being a prophet, and knowing that God had sworn with an oath to him that of the fruit of his body, according to the flesh, He would raise up the Christ to sit on his throne, he, foreseeing this, spoke concerning the resurrection of the Christ, that His soul was not left in Hades, nor did His flesh see corruption. This Jesus God has raised up, of which we are all witnesses. Therefore being exalted to the right hand of God, and having received from the Father the promise of the Holy Spirit, He poured out this which you now see and hear. For David did not ascend into the heavens, but he says himself: 'The Lord said to my Lord, "Sit at My right hand, Till I make Your enemies Your footstool." ' "Therefore let all the house of Israel know assuredly that God has made this Jesus, whom you crucified, both Lord and Christ." (Acts 2:22-36)If Jesus is not seated on David's throne then He has not been raised from the dead.
A lot of people miss the fact that physical things on earth under the old covenant were really just patterns of things in heaven. We see this plainly taught in the book of Hebrews regarding the matter of the temple. Cf. Heb 8:5; 9:23,24. Folks who look for a future physical temple on earth are obviously missing the real meaning of the physical temple. The same is true of "David's throne", which was merely a picture of God's heavenly throne where the Messiah now sits and reigns over the earth.
I realize futurists literalists have a difficult time dealing with the plain teaching in these verses because they are looking for a carnal fulfillment. They are like "Israel after the flesh" (1 Cor. 10:18) who still look for a fleshly king sitting on a carnal throne in earthly Jerusalem. But we also know that earthly Jerusalem is the city of Hagar and her spiritual offspring (Gal. 4:24,25). Why would you wish to live there?
"A solid confidence in the prosperity of the gospel is thus afforded us. Christ’s dominion “from the River to the ends of the earth” (Ps. 72:8) will not be the extension of Israel’s boundaries by military might, but the success of the Great Commission to make all nations His disciples (Matt. 28:18-20). It should be noted, in this regard, that although the Old Testament promises to Abraham speak of the promised land as Palestine, in the New Testament Paul sees the full scope of those promises (where the land of Palestine is merely a token of the final reward) as applying to all of creation. He says in Romans 4:13 that the promise was to Abraham and his seed “that we would be heir of the world”! When we follow through the teaching of Scripture about Israel, then, we see that God has promised His people – the church – that “The kingdom of this world is become the kingdom of our Lord and of His Christ” (Rev. 11:15). The true seed of Abraham, believers in Jesus Christ, will be more numerous than the sands of the sea or the stars of the sky..."
AMEN!