New Defender's Study Bible Notes
2:4 living stone. As not just the foundation rock (I Corinthians 3:11), but also as a living stone that could bring life and sustenance, Christ is the fulfillment of the type suggested by the rock smitten in the wilderness, which thenceforth brought life-sustaining water to God’s people (see Exodus 17:6; Numbers 20:8; I Corinthians 10:4).
2:4 chosen of God. The Greek word here for “chosen” (also in I Peter 2:9) is the same as that for “elect” in I Peter 1:2 and 2:6. Thus, the “elect of God” are those “chosen by God.” Note also John 15:16 and Ephesians 1:4.