Psalms 104:7

At thy rebuke they fled; at the voice of thy thunder they hasted away.

At God's rebuke the waters that covered the earth fled, and at the voice of His thunder they hasted away in retreat. As they retreated the mountains rose and the valleys sank down. In their flight they came to the place God had established and appointed for them.

There God fixed their bounds, setting limits for the waters in their appointed place. This exercise of command over the waters displays His power as part of His ordering and sustaining of nature.