Psalms 20:9

“Save thy people, etc.] The psalmist begins the psalm with petitions for himself, and closes it with prayers for the people of God; whom God has chosen for his people, taken into covenant to be his people, and given them to his son as such; these he has resolved to save, and has appointed Christ, and sent him into the world, to be the Saviour of them; and to them he makes known and applies the great salvation by his Spirit: so that this prayer was a prayer of faith, as are also the following petitions; and bless thine inheritance; the people whom the Lord has chosen for his inheritance, and has given to Christ as his portion, and are his peculiar possession; and these he blesses with all…”

“let the king hear--as God's representative, delivered to deliver. Perhaps a better sense is, "LORD, save the king; hear us when we call," or pray. Next: Psalms Chapter 21”

“Save, Lord - “Yahweh, save.” This is still an earnest prayer. Confident as they are of success and triumph, yet they do not forget their dependence on God; they do not forget that victory must come from his hand. There was, indeed, exultation, but it was exultation in the belief that God would grant success - an exultation connected with, and springing from prayer. Prayer is not inconsistent with the most confident anticipation of success in any undertaking; and confidence of success can only spring from prayer. Let the King - That is, let “God,” spoken of here as the Great King. The connection and the parallelism demand this interpretation, for to God only is this prayer addressed. He is…”

“Let the king - God, the supreme monarch, the king of kings, and in a peculiar manner the king of Israel. Next: Psalms Chapter 21”

“Save: etc. or, "O Jehovah, save the king; answer us when we call upon thee." Psa 118:25, Psa 118:26; Mat 21:9, Mat 21:15 let: Psa 2:6-10, Psa 5:2, Psa 24:7, Psa 44:4, Psa 74:12 Next: Psalms Chapter 21”

“(Heb.: v. 10) After this solo voice, the chorus again come on. The song is closed, as it was opened, by the whole congregation; and is rounded off by recurring to its primary note, praying for the accomplishment of that which is sought and pledged. The accentuation construes המּלך with יעננוּ as its subject, perhaps in consideration of the fact, that הושׁיעה is not usually followed by a governed object, and because thus a medium is furnished for the transition from address to direct assertion. But if in a Psalm, the express object of which is to supplicate salvation for the king, המלך הושׁיעה stand side by side, then, in accordance with the connection, המלך must be treated as the object; and…”