I highly recommend this book. Please understand that I love to read books on the doctrine of repentance. It is not a difficult read.
Here are a couple of quotes-
'Do you feel God would be dealing unfairly with you if you ever found yourself in hell? If you do you have not repented. I would emphasize that the test of repentance is this, that a man having looked at himself and his own heart and life, says to himself: "I deserve nothing but hell, and if God sends me there I haven't a single complaint to make. I deserve nothing better!" '
"Repentance means that you realize that you are a guilty, vile sinner in the presence of God, that you deserve the wrath and punishment of God, that you are hell-bound. It means that you begin to realize that this thing called sin is in you and that you long to get rid of it and that you turn your back on it in very shape and form. You renounce the world whatever the cost, the world in its mind and outlook as well as its practices, and you deny yourself and take up the cross and go after Christ. Your nearest and dearest and the whole world may call you a fool or say you have religious mania, you may have to suffer financially, but it makes no difference. That is repentance."