Adiaphora
Scott Clark's concept of QIRC -- the "Quest for Illegitimate Religious Certainty". See here.
Clark first supports his thesis that the dearth of rootedness in modern Reformed Christianity has come about through two interconnected false approaches to theology and piety, which he has called the quest for illegitimate religious certainty (QIRC) and the quest for illegitimate religious experience (QIRE). Falling into the former category would be both the impulse to make a litmus test for orthodoxy such issues as have not historically borne the weight of sine qua non for Reformed doctrine, such as a literal period of seven twenty-four hour days in the first chapter of Genesis; and also, the impulse to formulate doctrines that are in contradiction to essential Reformed tradition, such as the recasting of justification in accordance with the ideas of covenant moralism. Falling into the latter category would be the strains of piety that have come down from Anabaptist traditions, and the revivalism of Edwards and Whitefield, which Clark sees as organically connected to the revivalism of the nineteenth and twentieth centuries.
(Gotta get me that book, one of these days.)