William M. Greathouse writes:
The new man in Christ is therefore actually living a holy life in Christ and in the power of the Spirit. The old man he once was in Adam has ceased to be.
An incident in Augustine's early Christian life illustrates this. Before his conversion he had a mistress named Claudia. Shortly after he found Christ, Claudia saw him on the street in the city. "Augustine! Augustine!" she cried after her old paramour [lover]. Augustine paid no heed. "Augustine! Augustine!" she cried out again. "It is Claudia!"
"But it is no longer Augustine," he replied, as he continued on his way.
