An excellent and insightful study of the spiritual lessons we can learn from the world around us--particularly the world of farming and, to a lesser degree, nature. Some of the analogies are a bit simplistic, but then Flavel is explicitly addressing the farming community, an audience he views as rather simplistic.
Each discussion is between 4 and 8 pages of length (excellent for devotional use) and begins with a description of the natural phenomenon (sowing grain, for example), followed by an analysis of how that phenomenon is similar to a spiritual truth and application to Christian life. Flavel then includes a series of reflections from varying points of view (i.e., a worldly person's reflections, a backsliding Christian's reflections, a lazy person's reflections, a discouraged Christian's reflections, etc.), and then closes with a poem. I must confess, I found the poems rather underwhelming, but the application and reflections were quite good, and often convicting.
Flavel writes like a Puritan (that is, fairly densely), but is one of the more readable writers in that era, especially in the Banner of Truth editions (like the complete Works of John Flavel, which I used)--other editions (consisting of cheaply made photocopies of old public domain documents) are much harder to read. The use of quotation marks was a bit distracting at times (within a paragraph or section of quoted text, each line of the text begins and ends with quotation marks, even if the line breaks in the middle of the sentence), but as I understand it, it's a historically authentic editing choice. And anyway, I got used to it.
All in all, a great book, and well worth reading, especially if you like Puritan writers. I will close with what was probably my favorite passage in the whole book:
[...H]ere is matter of unspeakable comfort; though the flesh say, Ego deficiam, I will fail thee; though the world say, Ego decipiem, I will deceive thee; though the devil say, Ego eripiam, I will snatch thee away; yet as long as Christ saith, I will never leave thee, nor forsake thee, thy graces are secure in the midst of all these enemies.(from Chapter 13, "Upon the dangers incident to the corn from seedtime to harvest").
[...] Desponding, trembling soul! lift up thine eyes and look upon the fields; the corn lives still and grows up, though birds have watched to devour it; snows have covered it, beasts have cropped it, weeds have almost [choked] it, yet it is preserved. And hath not God more care of that precious seed of his own spirit in thee, than any husbandman hath in his corn? Hath he not said, "That having begun the good work in thee, he will perfect it to the day of Christ?" Hath he not said, "I give unto them eternal life, and they shall never perish." [...] Well then, be not discouraged, for thou dost not run as one uncertain, nor fight as one that beats the air. But "the foundation of God stands sure, having this seal--the Lord knows who are his." Though thy grace be weak, thy God is strong; though the stream seem sometimes to fail, yet it is fed by an overflowing fountain.