"He is the Rock, His work is perfect: for all His ways are judgment: a God of truth and without iniquity, just and right is He" (Deuteronomy 32:4).
Here in the song of Moses, which God instructed him to write for the children of Israel as they were about to enter the Promised Land (note Deuteronomy 31:19), is the first of at least 40 references in the Bible to God as the Rock. There are four others just in this song. In verse 15, He is the "Rock of [Israel's] salvation." In verse 18, He is "the Rock that begat thee." See also verses 30 and 31.
Note some of the other wonderful metaphors picturing God as our great foundation stone. He is "my strong rock" in Psalm 31:2, and "the rock that is higher than I" in Psalm 61:2. In Psalm 62:7, He is "the rock of my strength" and "the rock of my refuge" in Psalm 94:22. The prophet Isaiah calls Him "a great rock in a weary land" and "the rock whence ye are hewn" (Isaiah 32:2; 51:1).
During the wilderness wanderings, the Israelites were supplied continually with water from the rock, and the apostle Paul tells us "that spiritual Rock that followed them . . . was Christ" (I Corinthians 10:4). And, of course, Christ told His disciples that Peter's confession of Himself as the "Son of the living God" was the Rock upon which He would build His church (Matthew 16:16,18).
But to unbelievers He is "The stone which the builders rejected" (Matthew 21:42), "a stone of stumbling, and a rock of offense, even to them which stumble at the word" (I Peter 2:8). "Therefore," said Jesus, "whosoever heareth these sayings of mine, and doeth them, I will liken him unto a wise man, which built his house upon a rock: And the rain descended, and the floods came, and the winds blew, and beat upon that house; and it fell not: for it was founded upon a rock" (Matthew 7:24-25). HMM