Reading Darby is hard. I'd like to say it isn't, but it is. No sooner do you attempt to read Darby than you discover two features of his writing. First, he doesn't write to be understood so much as to think on paper. His writing is convoluted and poorly organized: paragraphs sometimes span several pages, sentences run on for miles, and long tangents appear every few pages.
Second, he's a brilliant writer. This was a man who spoke umpteen languages (including, apparently, fluent Maori) and spent his life in study. There's a good chance he was smarter than you, and it can be hard to fight through the convoluted prose of someone of superior intellect. It can be particularly unnerving when he includes Latin and Greek in the text: I have just a tiny smattering of Greek, and no Latin at all. Getting past some of those pages has been hard.
And it's not just that he's a brilliant writer (although he is): another problem is that he wrote almost 200 years ago---language has changed a lot in that time. Darby wrote just about the same time as Jane Austen, and it's worth keeping that in mind when reading his articles. I read an article online a few years ago that argued Darby was anti-intellectual. They were arguing his teachings deliberately hid from secular history and scholarship. This astonishing statement was based on this quote:
History was not written in heaven. I believe that the attempt to interpret prophecy by history has been most injurious to the ascertaining of its real meaning. When we have ascertained, by the aid of the Spirit of Christ, the mind of God, we have, as far as it be history, God's estimate of events, and their explanation. But history is man's estimate of events, and he has no right to assume that these are in prophecy at all, and it is clear that he must understand prophecy before he can apply it to any: when he understands it, he has what God meant to give him, without going farther. I do not admit history to be, in any sense, necessary to the understanding of prophecy. I get present facts, and God's moral account of what led to them, and thereby His moral estimate of them: I do not want history to tell me Nineveh or Babylon is ruined, or Jerusalem in the hands of the Gentiles. Of course, where any prophecy does apply to facts, it is a true history of those facts; but it is much more. It is the connection of those facts with the purposes of God in Christ, and whenever any isolated fact, however important in the eyes of man, is taken as the fulfilment of a prophecy, that prophecy is made of private interpretation; and this I believe to be the meaning of that passage. Of course, when any prophecy is fulfilled, the fulfilment is evidence of its truth, but the Christian does not need this; and evidence of truth and interpretation are two very different things. ("Notes on Revelation" )
The author had latched onto the quote, "I do not want history to tell me Nineveh or Babylon is ruined, or Jerusalem in the hands of the Gentiles" and concluded Darby was afraid to study history. Of course, the real problem was the author's own [barely functional] illiteracy. He completely failed to grasp that "want" 200 years ago meant "lack" as opposed to "desire". What Darby was actually saying is, it's not necessary to have a thorough grasp of history to read and understand Scriptural prophecy. He was claiming that Scriptural prophecy is essentially self-contained. He was certainly not claiming that Scripture is historically inaccurate, but that's the general gist the author was attempting to give.
Besides his tendency to "think on paper" rather than striving for clarity, and his use of dated English (hardly his fault when he died in 1882), one difficulty with reading Darby is the context in which he wrote. A good deal of his papers are tracts, letters, or articles written in a theological controversy of the time. This can be more than a little annoying, as we rarely have the papers, articles, or tracts to which he is replying. So an article by JND written in response to Cardinal Newmann might seem a little difficult to get into, if we haven't the original article.
I think, though, that the danger here is more than just the lack of context; the danger is that it can be hard to catch the relevance of an article entitled "Remarks on a Tract by Someone-or-other". Worse, it can be hard to get past several pages of specific replies to objections to get to the real point of the paper: not the specifics that Someone-or-other brought up, but the arguments from Scripture that strike at the heart of the argument.
See, the real value of reading Darby is not to get a hold of some doctrinal position or grasping some point of theology. The real value is that this was a man who was perhaps unequaled in his ability to point out the implications of some idea or another. Darby was simply brilliant in his ability to get to the root of a problem; to see how the implications of a relatively minor point would affect, colour, and influence positions on much more major points. Darby had a real gift for seeing watersheds for what they are: minor points that had major implications.
When I first read Darby, I wondered why he spent so much time beating on a small point here or there while more or less ignoring much more prominent points. Eventually I came to see that he was correctly seeing that the "minor" points had much larger implications than what I had thought were much "greater" questions. His insistence on the imminent return of Christ was not a shibboleth: it was a result of his [correct] appraisal that this minor doctrinal point has major moral implications. Is the imminent return of Christ a major theological question? not really. But it has major moral outcomes.
But the good news is, reading Darby is worth the effort.
I set out to read Darby about 12 or 13 years ago, because so many people worshiped the man, and at the same time so many vilified him. I had to read this stuff for myself, to try and figure out what the deal was. I started with a set of Notes and Comments on Scripture, which was given me as a gift. I didn't read the whole set, but I read bits here and there. After that, I was given Volumes 16 & 17 of The Collected Writings of J. N. Darby; I read those, then was given Volumes 1 & 3. Shortly after I finished those, I found a used copy of Volume 12. Then I just bit the bullet and bought all 34 volumes plus the index. At this point, I've read Volumes 1--24 and am partly through Volume 25. So I've read enough to have an idea how to "break the code" and get into the books. That's really why I started out with "J. N. Darby's Greatest Hits": I thought I'd share my favourites with both my readers.
So if you're willing to listen to me, I can tell you the best place to start is Volume 12 (Evangelic 1). That's a collection of his gospel messages. They're short, clear, and fairly simple to grasp: a lot of them are transcripts of sermons he preached, and his sermons were much "better" than his writing. He apparently had an easier time being understood when he could see his audience in front of him.
But the real value of Volume 12 is this: it gives you a look into his mind. Darby was fascinated with God's love and His grace. While following generations have generally painted him as some sort of legalistic fanatic, his own words are much more saturated with his basking in God's love than in blasting people who disagreed with him. If you don't start at the beginning, the rest gets blurry. To Darby, the beginning was the Gospel. So read Volumes 12 (and 21) first.
After Volume 12, I would recommend Volume 16 (Practical 1) and Volume 2 (Prophetic 1) as the next steps. The practical volumes (Vols. 16 & 17) are what we now call "Christian Living" books. I found Volume 16 a lot better than 17, but that might just be me. But I would suggest getting into Volume 2 fairly quickly too. Darby was a monster of prophecy, and his prophetic works are sheer brilliance.
I would suggest the next step is Volume 10 (Doctrinal 3). This is a volume almost entirely dedicated to Darby's writings on Law. It is well worth reading and re-reading, but is probably best read after Vols. 12, 16, and 2.
If you really want to, you can read Volume 1 (Ecclesiastical 1) right at the start, but I'd recommend against it until you get used to Darby's unique brand of English via Volumes 12, 16, and 2. Darby's ecclesiastical writings are brilliant no doubt, but they're also detailed and long. There's a lot to be learned there, but it can be hard to dig out unless you've learned to read Darby already.
So I'm going to put up more of JND's greatest hits, but I wanted to get this out there first.