Let me not be ashamed, O Lord, for I have called upon thee - That is, I have reposed entire confidence in thee, and in thy promises, in the time of trial; let now the result be such as to show that I had reason thus to trust in thee; that thy character is such that the persecuted and the afflicted may always find thee to be a safe and secure refuge. In other words, Let me not be disappointed, and thus be made “ashamed” before men, as if I had put my trust where no relief was to be found, or where there was nothing to authorize an act of unreserved confidence. See the notes at Psalms 25:2-3.
Let the wicked be ashamed - Let them be disappointed in that on which they had put their trust; let it be seen that they, in their wicked plans, had no safe ground of confidence. They rely on their strength; their skill; their courage; their resources; and not on God. Let it now be seen that these things constitute no safe ground of trust, and let not others be encouraged to follow their example by any success that shall attend them in their designs.
And let them be silent in the grave - Margin, “let them be cut off for the grave.” Hebrew: “for Sheol.” The more correct translation is that which is in the text, “Let them be silent.” That is, let them go down to the grave - to “Sheol” - to the “underworld” - to the “land of silence.” On the meaning of the word used here - “Sheol,” the grave - see the notes at Isaiah 14:9; compare the notes at Job 10:21-22; and the notes at Psalms 16:10. This is represented as a land of “silence.” This idea is derived from “the grave,” where the dead repose in silence; and the meaning here is, let them be cut off and consigned to that land of silence. It is a prayer that the wicked may not triumph.