Man, in his state of innocency, had freedom, and power to will and to do that which was good and well pleasing to God; but yet, mutably, so that he might fall from it. - WCF 9.2
This paragraph is the first of four that is dealing with human nature in its four-fold state.
Brief overview of what that means?
The four-fold state is drawn from the Bible. Augustine wrote a book on the will which showed the clear lines of demarking. The four states that a Christian exists. (a) able to sin, able not to sin (posse peccare, posse non peccare); (b) not able not to sin (non posse non peccare); (c) able not to sin (posse non peccare); and (d) unable to sin (non posse peccare).
Boston speaks of our (1) primitive integrity, (2) our entire depravity, (3) our begun recovery and (4) our consummate happiness.
Below we have gathered some resources on, what Boston calls, primitive integrity:
The State of Innocence by Thomas Boston
The Lord God formed man out of the dust of the ground by John Flavel
Man's Will Before and After the Fall by Robert Shaw
Man, in his state of innocency by Derek Thomas
Man, in his state of Innocency by A. A. Hodge
Of the State of Adam Before the Fall by John Owen
God's Will, Man's Will and Free Will by Ernest C Reisinger
Free Will and Man's Four-Fold State by Ernest C Reisinger
The Will Before and After the Fall by William Cunningham
The Positive Purity of the Original State of Man by Tom Nettles
Why Did Adam and Eve Sin If They Did Not Have a Sinful Nature? by Martyn Lloyd-Jones
Question on The State of Man's Will Before the Fall by Reformation Theology
The State of Innocence by AU YEONG HAU TZENG
Human Nature in its Fourfold State (eBook) by Thomas Boston
Jonathan Edwards on Adam Before the Fall @Reformed Forum Participants: Camden Bucey, David Filson, Jeff Waddington
9.2: The State of Innocency by Jerusalm Chamber (MP3)
The 1689 On Free Will (9.1-3) by Doctrine and Devotion