Neither is there any rock. — This was a favourite simile among the inspired song-writers of Israel. The image, doubtless, is a memory of the long desert wandering. The steep precipices and the strange fantastic rocks of Sinai, standing up in the midst of the shifting desert sands, supplied an ever present picture of unchangeableness, of majesty, and of security. The term rock, as applied to God, is first found in the Song of Moses (Deuteronomy 32:4; Deuteronomy 32:15; Deuteronomy 32:18; Deuteronomy 32:30-31; Deuteronomy 32:37), where the juxtaposition of rock and salvation in 1 Samuel 2:15 — he lightly esteemed the rock of his salvation — seems to indicate that Hannah was acquainted with this song or national hymn of Moses. The same phrase is frequent in the Psalms.
That the term was commonly applied to God so early as the time of Moses we may conclude from the name Zurishaddai: “My rock is the Almighty” (Numbers 1:6); and Zuriel: “My rock is God” (Numbers 3:35). — Speaker’s Commentary.