The Christian in Complete Armour is William Gurnall’s exposition of Ephesians 6:10-20, a long series of sermons he preached at Lavenham in Suffolk. It appeared in three volumes in 1655, 1658 and 1662, and had reached a sixth edition by the time Gurnall died.
Check which edition you are buying
This matters more than usual, so deal with it first.
The listing this review points at is a cheap ebook reprint of a public-domain text with no stated editor, no page numbers, and no indication of which source it was set from. It is readable, and it is legitimate in the sense that the text is genuinely Gurnall’s, but you have no way of knowing what you are getting.
Two editions are worth owning instead. Banner of Truth publishes the unabridged text based on the 1864 edition, which carries an introduction by J. C. Ryle. Banner also published a revised, abridged three-volume set in 1988 that puts Gurnall into modern English. If the seventeenth-century prose defeats you, the abridgement is the honest answer rather than giving up.
Why the book has the reputation it has
Spurgeon said more sermons had been suggested to him by this book than by any other work outside Scripture. John Newton said that if he could read only one book besides the Bible, this would be it. Those are not small endorsements, and they are the reason it survived.
What Gurnall does is take one passage, the armour of God, and refuse to move on. Each piece gets exhaustive treatment: what it is, what it protects, how the enemy attacks that specific point, how a believer fails to use it. The result is less a book to read through than a book to work in.
What reading it is actually like
Hard. Gurnall writes dense seventeenth-century English, packed with subordinate clauses and extended metaphors. An earlier version of this review called it “Old English,” which is wrong: Old English is Anglo-Saxon and unreadable without training. This is Early Modern English, roughly Milton’s era. Difficult, not foreign.
He is also relentlessly practical despite the style. Gurnall keeps asking what a discouraged believer should actually do, and his pastoral instincts are better than most modern writing on spiritual warfare, which tends to drift toward technique.
How to use it
Not front to back at speed. A page or two at a time, slowly, with something to write with. The unabridged edition runs well over a thousand pages, which is why plenty of people own it and few finish it, and why treating it as a reference to dwell in is more realistic than treating it as a reading project.
Who it suits
Worth it for a reader who wants depth on spiritual conflict and is willing to work for it, and for anyone whose devotional reading has gone shallow. Not the place to start if you have never read a Puritan, and not the book to hand a new believer.
Bottom line
One of the greatest practical works the Puritans produced, and still the fullest treatment of Ephesians 6 in English. Buy a proper edition rather than an anonymous reprint, and read it slowly or not at all.
Check the current price of this ebook edition on Amazon
Or a full print edition of The Christian in Complete Armour