God is at work here to gather a people for himself. Whenever we come to church we're given the Gospel. The Gospel is the announcement that the man Jesus of Nazareth, who ate with sinners and forgave their sins, healed the sick, raised the dead, was crucified for our sins and raised victorious over death, is Lord and Christ - that Jesus is the son of God who rules over creation.
Everytime we come to church that message is given to us to believe, to hold fast to, and to cherish as our own. Through the proclamation of that message, through the waters of baptism, through the forgiveness of sins, and through the Lord's Supper, the announcement that Jesus is Lord becomes personal. Because he washes us, forgives us, and gives us his body and blood as the new covenant, Jesus is not only Lord over creation; he is also our Lord. God is at work, through the proclamation of the Gospel to make us his people - a people who are his treasured possession in Christ Jesus.