What is the meaning of Psalms 2:7 before Jesus?
The meaning of Psalms 2:7 before Jesus is, God annointed David to be king as 1 Samuel 16:12-13 show. Jesus' declaration of his own annointment is shown in Luke 4:18. Isaiah 61:1
1 Samuel 16:12-13 ASV
And he sent, and brought him in. Now he was ruddy, and withal of a beautiful countenance, and goodly to look upon. And Jehovah said, Arise, anoint him; for this is he Then Samuel took the horn of oil, and anointed him in the midst of his brethren: and the Spirit of Jehovah came mightily upon David from that day forward. So Samuel rose up, and went to Ramah.
Luke 4:18 Aramaic Bible in Plain English
“The Spirit of THE LORD JEHOVAH is upon me, and because of this he has anointed me to preach The Good News to the poor; he has sent me to heal broken hearts and to proclaim liberty to captives, vision to the blind, and to restore the crushed with forgiveness,”
Isaiah 61:1 ASV
The Spirit of the Lord Jehovah is upon me; because Jehovah hath anointed me to preach good tidings unto the meek; he hath sent me to bind up the broken-hearted, to proclaim liberty to the captives, and the opening of the prison to them that are bound;
This was also confirmed in Acts 4:24:26 shows. God selected David to be king. God did the same with David's son Solomon.2 Samuel 7:12-14.
Acts 4:24-26 ASV
And they, when they heard it, lifted up their voice to God with one accord, and said, O Lord, thou that didst make the heaven and the earth and the sea, and all that in them is: who by the Holy Spirit, by the mouth of our father David thy servant, didst say, Why did the Gentiles rage, And the peoples imagine vain things? The kings of the earth set themselves in array, And the rulers were gathered together, Against the Lord, and against his Anointed:
2 Samuel 7:12-14 ASV
When thy days are fulfilled, and thou shalt sleep with thy fathers, I will set up thy seed after thee, that shall proceed out of thy bowels, and I will establish his kingdom. He shall build a house for my name, and I will establish the throne of his kingdom for ever. I will be his father, and he shall be my son: if he commit iniquity, I will chasten him with the rod of men, and with the stripes of the children of men;