I'm getting started way late in this thread, and I haven't read all of it. However, it is my opinion that the false understanding of what the soul is, has led to much confusion within Christianity. It also leads to many false doctrines.
So I will attempt to explain the soul in simple terms for all the readers. I will be more specific with scripture if people respond further....
The soul (nephesh OT and psuche NT) in simplest terms is a person.
A living person on this earth is a soul. They have a body (the flesh) and a spirit (ruach OT and pneuma NT). The spirit is the life force that we all have. When we die the spirit leaves the flesh. At this time the soul and the spirit are synonyms, and the words are used interchangeably in the scriptures.
At the resurrection, the spirit will be reunited with incorruptible flesh for those in Christ and it will be reunited with corruptible flesh for those outside of Christ.
The soul is not immortal. Immortality (eternal life) is a gift. Those in Christ have two spirits: theirs and the Holy Spirit.
Now the Greek and Hebrew are very similar to the English word "soul". We use this word properly all the time.
“The stadium is filled with 50,000 souls.” (the soul is a person)
“Grandma is a good ole soul.” (the soul is a person)
“When I die, my soul will live with God.” (my personal spirit which has been separated from my flesh lives with God)
The concept is really quite simple, but the Church teachings on this subject have really messed it up. Comments anyone?