You'll see there is a tab called "Writings" on the header. If you look there, you will find a page with my 2011 CCL lectures in PDF format for download.
The first is entitled: "Cultural Amnesia: What Makes Pietism Possible?"
The second is: "Grace Restores & Perfects Nature: Herman Bavinck and 21st Century Cultural Transformation."
Both of these lectures critique, from different angles, the Two Kingdoms Theology of Drs. Michael Horton and David VanDrunen of Westminster Seminary California. I hope they will be of benefit to you!