Passage
At thy rebuke they shall flee: at the voice of thy thunder they shall fear.
At thy rebuke they shall flee: at the voice of thy thunder they shall fear.
Psalms 103:5 Who hast founded the earth upon its own bases: it shall not be moved for ever and ever.
Psalms 103:6 The deep like a garment is its clothing: above the mountains shall the waters stand.
Psalms 103:7 At thy rebuke they shall flee: at the voice of thy thunder they shall fear.
Psalms 103:8 The mountains ascend, and the plains descend into the place which thou hast founded for them.
Psalms 103:9 Thou hast set a bound which they shall not pass over; neither shall they return to cover the earth.
The verse centers on "rebuke", "shall", "flee", "voice", "thunder", and "fear". It is saying that the verse draws attention to "rebuke" and "shall", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 6's "The deep like a garment is its..." into verse 8's "The mountains ascend and the plains descend...", so "rebuke" and "shall" belong inside that flow. In Psalms context, the local focus is worship, trust, the LORD's kingship, and covenant mercy.
A plain takeaway is to answer the verse's own emphasis on "rebuke" and "shall" with trust shaped by these words, not by a vague optimism outside the passage.