What does Psalm 28:9 mean?

David prays for God to save Israel, His inheritance. Someday, the Lord will eternally save members of every tribe of Israel to be His people (Romans 11:25–32). They will enter Messiah's kingdom and enjoy peace and prosperity. They will be His family. Isaiah 40:11 predicts the salvation of Israel and states: "He [Messiah] will tend his flock like a shepherd; he will gather the lambs in his arms; he will carry them in his bosom, and gently lead those that are with young."

That this psalm uses shepherding images is fitting, given David's experiences. As a shepherd, David knew all about the process; he mentions in Psalm 23 that the Lord, his shepherd, led him beside still waters and along paths of righteousness (Psalm 23:2–3). A good shepherd knows each of his sheep by name, and he feeds his sheep. As a caring shepherd, he leads his sheep and often carries them on his shoulders.