"For I am the least of the apostles ... But by the grace of God I am what I am ..." (1 Corinthians 15:9, 10)
Every humble and devoted believer in Jesus Christ must have his own periods of wonder and amazement at this mystery of godliness - the willingness of the Son of Man to take our place in judgment so that the people of God could be a cleansed and spiritual people!
If the amazement has all gone out of it, something is wrong, and you need to have the stony ground broken up again!
The Apostle Paul, one of the holiest men who ever lived, was not ashamed of his times of remembrance and wonder over the grace and kindness of God. He knew that God did not hold his old sins against him forever!
Knowing the old account was all settled, Paul's happy heart assured him again and again that all was well.
He could only shake his head in amazement and confess: "I am unworthy to be called, but by His grace, I am a new creation in Jesus Christ!
I make this point about the faith and assurance and rejoicing of Paul in order to say that if that humble sense of perpetual penance ever leaves our justified being, we are on the way to backsliding!
~A. W. Tozer~