I have been greatly enjoying listening to a series by Derek Thomas on Pilgrim's Progress. I have read this book more times than any other apart from the Bible. Every time I have learned more and never failed to enjoy this compelling allegory (a story that is a picture) of the Christian life.
You can hear the series on the following link:
Or go to the Ligonier Ministries web site, Renewing your Mind, and go to Ministries, then to Renewing Your Mind Broadcast, begin at 13th June 2016.
Or down load the app to your phone and access the talks that way.
They are offering the talks for purchase and there is an on line courses you can buy, but you can listen to the talks free of charge.
I suggest that you down load them to 'itunes', or what ever you use, as soon as possible, then you will have the talks if they remove them.