From the Introduction by Andrew Murray:
There is but one book in the language admitted by all to be the standard one on "Sanctification." It is the work of the Rev. Walter Marshall, published in 1692, "The Gospel Mystery of Sanctification." It has at all times received the highest praise from men of eminence both as theologians and as saints.
It is much to be regretted that the book is not better known among the members of our Christian churches. This may partly be accounted for by the author's style and treatment of his subject. His editors admit that his style is at times obscure, and that the book requires a more than ordinary attention to read it with profit. According to the fashion of the time, the argument is so broken down into divisions and subdivisions, that it is only by continually referring back and marking his stages carefully that the reader can keep hold of the thread. Such writing is not only wearying, but gives occasion to frequent repetition.
What appears to me, however, specially to hinder the interest and usefulness of the work is the introduction of questions, which are indeed of importance as connected with the subject, but still distract the attention of the earnest inquirer who wants a plain answer to the question, how he can be made holy? On this account I have often felt that an abridgment, in which subordinate points were only indicated in passing, and prominence given to the teaching on Sanctification which gives special value to the book, might be the means of giving it a wider circulation and influence.