The LORD liveth; and blessed be my rock; and let the God of my salvation be exalted. (Psalm 18:46)
Beneath the surface-appearance of physical reality - underlying all the vicissitudes and changes that are constantly taking place in the universe - we can discern a greater and unchanging "ground of being," the Source of Life and the foundation of all.
In this pasuk (verse), King David refers to the LORD as his "Rock," (tsur) a metaphor often employed in Scripture to depict God's constancy, strength, power, and presence (see Deut. 32:4; cp. 1 Cor. 10:4).
Experiencing God as our Rock means being aware that He is the solid foundation - or underlying reality - in every life circumstance and trial we might face. The God of Israel is the "Living God," the One who is exalted even in the midst of the storms of our lives; whoever believes on Him shall not be ashamed (Rom. 9:33).