The substance of the following essay was delivered from the pulpit, in the form of a sermon, more than twenty years ago, and subsequently published. In consequence of repeated solicitation, from some individuals in your number, I have thought proper to alter its form, to enlarge its limits, and to adapt it, according to my best judgment, to more general utility. It has long appeared to me that a more ample discussion of this subject than I have hitherto seen, is really needed. And if the present volume should be considered as, in any tolerable degree, answering the desired purpose, I shall feel myself richly rewarded for the labour which has attended its preparation. – Samuel Miller, from the Preface.