18. Yea, one thing more I think I may suppose in all or most that will read this book; that you take on you also to believe in Jesus Christ, and in the Holy Ghost the Sanctifier, and that the Scriptures are the word of God. And if you do so indeed, I may then hope that my work is in a manner done, before I begin it: but if you do it but opinionatively and uneffectually, yet God and man may plead with you the truths which you profess. Having told you what I presuppose in you, I proceed now to the directions. But I again entreat and charge thee, reader, as thou lovest thy soul, and wouldst not be condemned for hypocrisy and sloth, that thou dost not refuse to put in practice what is taught thee, and show thereby, that whatever thou pretendest, thou art not willing to do thy part for thy own salvation, no not in the most reasonable, necessary things.[15] _Direction_ I. If thou be truly willing to be sanctified and a child of God, remain not in a state of ignorance; but do thy best to come into the light, and understand the word of God, in the matters of salvation. If knowledge be unnecessary, why have we understanding?[16] and wherein doth a man excel a beast? If any knowledge at all be necessary, certainly it must be the knowledge of the greatest and most necessary things: and nothing is so great and necessary as to obey thy Maker, and to save thy soul. Knowledge is to be valued according to its usefulness. If it be a matter of as great concernment to know how to do your worldly business, and to trade and gather worldly wealth, and to understand the laws, and to maintain your honour, as it is to know how to be reconciled unto God, to be pardoned and justified, to please your Creator, to prepare in time for death and judgment, and an endless life, then let worldly wisdom have the pre-eminence. But if all earthly things be dreams and shadows, and valuable only as they serve us in the way to heaven, then surely the heavenly wisdom is the best. Alas, how far is that man from being wise, that is acquainted with all the punctilios of the law, that is excellent in the knowledge of all the languages, sciences, and arts, and yet knoweth not how to live to God, to mortify the flesh, to conquer sin, to deny himself, nor to answer in judgment for his fleshly life, nor to escape damnation! As far is such a learned man from being wise, as he is from being happy.