In this recording Korey Maas (Lutheran), Miles Smith (Anglican), and D. G. Hart (Presbyterian) take the temperature of confessional Protestants.  The notion of a "hot" Protestant has less to do with sexual appeal than with intense piety.  Michael Winship's book on the Puritans uses "hot" to describe those English Protestants who were eager to carry out the reformation in the Church of England as well as in the lives, families, and vocations of believers.  A similar tendency was evident in the most zealous of Scottish Protestants who wanted Presbyterian rather than episcopal government in the Church of Scotland.  That historical record suggests that Presbyterians are more prone to run a fever, which is ironic since for much of the twentieth century Presbyterians had the reputation of being "God's frozen chosen."  

Hotness is not peculiar to Presbyterianism, though.  Lutherans have had their challenges with Pietists, another set of Protestants who challenged the official and seemingly cold versions of Lutheranism.  Meanwhile, Anglicans have always had to decide whether the metric of high church or low church is inversely proportional to the heat of Anglican piety.  Low church Anglicans have often favored hotter forms of devotion and in the twentieth century that preference veered into charismatic expressions of piety.  

Lots of discussion in this episode.  Listeners will have to judge the degree of heat or light.