The Psalm ends, as it began, with ascribing glory to God, as God in covenant with Abraham, Isaac, and Jacob. The horn of all earthly power must be broken, but Christ, the horn of salvation to his people, must be exalted. Daniel 7:21, etc. Luke 1:68-69.
Related Commentaries of Psalms 75:9
Psalms 75:9-10
9 But I will declare for ever; I will sing praises to the God of Jacob.
10 All the horns of the wicked also will I cut off; but the horns of the righteous shall be exalted.