This psalm pictures God as King- 47:2, 6, 7.

His dominion is "all the earth"- 47:2, 7; "the nations"- 47:8. He subdues peoples and nations- 47:3- and therefore all nations celebrate HIs reign as king- 47:1, 5.

The reception given to Him is the reception that kings received when coming to the throne- I Sam. 10:24; II Sam. 15:10; I Kings 1:39; II Kings 9:13; 11:12.

In a sense each of the Psalms tell the gospel story and Psalm 47 is no different.
47:1 mentions joy because God reigns and the word for joy used in the LXX of the OT is the same word used of response to Jesus in Luke 1:44.
47:1, 2, 7 All the nations are subject to Jesus- Matthew 25:32; 28:18-20
47:3 Christ will put all enemies beneath His feet- I Cor. 15:24-26
47:4 Just as God chose Israel, He chose us- Eph. 1:4
47:4 He prepares Israel's inheritance as He prepares us- I Peter 1:4
47:5 Jesus ascended to God- John 20:17; Acts 2:34; Eph. 4:8, 9, 10.
47:2, 6, 7 Jesus is King- Matt. 2:2; 27:11; John 19:19-22
47:9 His people will include all nations- Romans 4; Gal. 3
Our response to this is to Praise God!!!!!