When Christ told Peter that Peter was a pebble, Peter got it.  He understood how the church was going to work.  In 1 Peter 2:4-9  he goes into detail about "stones, and rocks" and the allegory of building a church on the foundation corner stone that is Jesus Christ.  I am going to pick out some phrases.  You probably need to read it all.

Verse 5:  "You also, as lively stones, are built up (into) a spiritual house, a holy priesthood, to offer up spiritual sacrifices, acceptable to God by Jesus Christ."

Verse 9: "But you are a chosen generation, a royal priesthood, a holy nation, a peculiar people; that you should show forth the praises of him who has called you out of darkness into his marvelous light:"

In these two verses we, the members of the church,  are described.  Peter calls us:
1.  Lively stones.   We don't sit and soak.  We do stuff.  Good stuff.
2.  Built up.   We learn and grow.
3.  A spiritual house.   Together we form a church where God dwells.
4.  A holy priesthood.  We are our own priest.  Each one of us is holy due to Christ within.
5.  Chosen generation.  God chose us before we chose him.
6.  Royal priesthood.   Jesus is King.  We are joint heirs.  Royal.
7.  Holy Nation.   This is probably referring to the Jews who are now Christians and all of us as well.
8.  Peculiar people.  I love this.  I am definitely peculiar.  We are all very different from the world.

Peter says the first point of all that is to offer up spiritual sacrifices.  (Not sheep, lambs or doves)  And he says that the second point is that we show others the praises of God.  Because he called us out of darkness.  Into His marvelous light.  Marvelous.  Peter said we had become something special to God.