James 1:21 Wherefore lay apart all filthiness and superfluity of naughtiness and recieve meekness the engrafted Word, which is able to save your souls.
Once you are born again, your spirit has been reborn. But God is not finished -- He is just beginning. You need to "work out your own salvation with fear and trembling" {Philippians 2:12}. In other words, you soul needs to be saved. The soul is often defined as the mind, the will, and the emotions. Each of these areas needs salvation.
The Holy Spirit works relentlessly to transform the whole man into God's perfect will. This process is called sanctification. When your soul is renewed with His Word, you think His thoughts and not your own. Submit yourself to be Holy Spirit and allow Him to change every thought and motive.