“Simon himself believed and was baptized. And he followed Philip everywhere, astonished by the great signs and miracles he saw.” Acts 8:13
Even though Simon believed and was baptised, we find that he was still full of bitterness and captive to sin. The “thought in his heart” had not changed as a result of his conversion. It is possible to go through the outward performance of faith and even be baptised but more is required to change the thoughts of our hearts. Simon wasn’t even aware there was a problem. How aware are we of what is in our hearts?