Preface. It will be the duty of those who are endowed with quicker and better understandings, in whose case the former books are sufficient, and more than sufficient, to effect their intended object, to bear with me with patience and equanimity whilst I attempt with more than ordinary diligence to tear up and eradicate depraved and ancient opinions hostile to the truth of piety, which the long-continued error of the human race has fixed very deeply in unenlightened minds; co-operating also in this, according to my little measure, with the grace of Him who, being the true God, is able to accomplish it, and on whose help I depend in my work; and, for the sake of others, such should not deem superfluous what they feel to be no longer necessary for themselves.  A very great matter is at stake when the true and truly holy divinity is commended to men as that which they ought to seek after and to worship; not, however, on account of the transitory vapor of mortal life, but on account of life eternal, which alone is blessed, although the help necessary for this frail life we are now living is also afforded us by it.