In today's Gospel reading from Mark 6 at Mass, we heard the story of how King Herod came to order the beheading of John the Baptist. Herod was the one who had John arrested and bound in prison on account of Herodias, the wife of his brother Philip, whom he had married. John had said to Herod that it's not lawful for him to have his brother's wife, so Herodias harbored a grudge against him and wanted to kill him.
Herod feared John, knowing him to be a righteous and holy man, and kept him in custody, yet he liked hearing him speak. [Here we see that Herod knew righteousness and holiness, and was even attracted to John. He feared him perhaps because he realized that he was guilty.]
On Herod's birthday, he gave a banquet and his own daughter came in and performed a dance. The king was so delighted that he promised to grant her whatever she asks of him. She went out to her mother and asked what she should ask for and her mother said "the head of John the Baptist." The girl hurried back to the king and made her request. Herod was deeply distressed, but because of his oaths and the guests present, he did not wish to break his word to her. This was how John got beheaded. [We see that Herod had his conscience, but he overrode the good voice he heard and followed the evil one in him.]
We all have a conscience. The good voice comes from God and the evil one from the Evil One. It's easy to ignore or smother the gentle good voice and pay attention only to the disruptive evil voice ~ just like the news: the bad news is pretty much all we get to hear. There is one antidote though ~ the Holy Spirit. As we are drawn closer to the Lord, the Holy Spirit purifies (sharpens) our conscience to the point that it works like a message filter, allowing only the good voice through and blocking the evil one.