Adult Bible Study - Being Lutheran - Chapter 1: Closed

We've started a congregation wide Bible Study based on the book "Being Lutheran" by Rev. A. Trevor Sutton.  Each session will be based on one of the chapters of this book.

https://smile.amazon.com/Being-Lutheran-Trevor-Sutton/dp/0758651783/ref=sr_1_1?ie=UTF8&qid=1495564330&sr=8-1&keywords=being+lutheran

This bride of Christ, the Church, is open because of the Gospel.  But how much has it become a closed worship social group?  How can we be opened by the Gospel to proclaim it openly?