I will warn you that this is a long post but it contains a lot of information if you have ever wondered why some churches stick to a defined system of Scripture readings for their Sunday services. I have shamelessly taken the following from the blog of Pastor Paul McCain, of Concordia Publishing House, and I will let him lead us through this explanation of a lectionary (I did not include links to everything in the following and if you are interested, please go to Pastor McCain’s blog, Cyberbrethren):

The other day a person asked us here at Concordia Publishing House where, exactly, did the lectionary systems Lutherans use today come from. Great question! My colleague, Rev. Scot Kinnaman, prepared a very helpful summary history that I thought I would pass along here. I added just a bit to it here and there. As Scot notes elsewhere when he…