A Vision is now to occupy our attention, whose obscurity so deterred the Jews that they forbade every attempt to explain it. But God appeared to his Prophet either in vain or not in vain: it is most absurd to suppose the former -- then if the vision is useful, it is necessary for us to attain at least a partial understanding of it. If any one object that the vision was exclusively intended for the Prophet -- the objection is easily answered, for what the Prophet wrote was clearly for the use of the whole Church. Now, if any one asks whether the vision is lucid, I confess its obscurity, and that I can scarcely understand it: but yet into what God has set before us, it is not only lawful and useful but necessary to enquire. Base indeed would be our sloth should we willingly close our eyes and not attend to the vision. We shall perhaps but skim the surface of what God wills: yet this is of no small moment, and not only a moderate but a slight degree of understanding may suffice for this. Thus briefly do I finish my preface, and come to the words of the Prophet: --