Living Stones Being Built Into a Spiritual House

This Sunday our Pastor will be preaching. He will take a look at 1 Peter chapter 2 verses 2
4-10 under the heading ” Living stones being built into a spiritual house”.

Why does Peter describe Christians as living stones? What is the spiritual house to which he refers? What is the nature of that spiritual house? What are the spiritual sacrifices to which Peter refers? Who are the priests?