Adam Clarke on Psalms 28:9

Save thy people - Continue to preserve them from all their enemies; from idolatry, and from sin of every kind.

Bless thine inheritance - They have taken thee for their God; thou hast taken them for thy people.

Feed them - רעה raah signifies both to feed and to govern. Feed them, as a shepherd does his flock; rule them, as a father does his children.

Lift them up for ever - Maintain thy true Church; let no enemy prevail against it. Preserve and magnify them for ever. Lift them up: as hell is the bottomless pit in which damned spirits sink down for ever; or, as Chaucer says downe all downe; so heaven is an endless height of glory, in which there is an eternal rising or exaltation. Down, all down; up, all up; for ever and ever.