In my opinion, this is the finest treatment of the Puritan doctrine of "seeking salvation" or "preparation for salvation." Edwards did not originate this teaching, but he was a strong and capable advocate of it. Most of the English Puritans taught it, as did Edwards' grandfather, the great Solomon Stoddard, whose book "A Guide To Christ" was called by Dr. Gerstner "a classic."
This teaching was once the heart of Reformed evangelism, but it is largely unknown today, even in Reformed circles. You can find it in Thomas Watson's "Heaven Taken by Storm." Edwards' most well-known sermon on this topic is "Pressing Into the Kingdom."