On this day we celebrate Holy Pentecost in our church. Fr. Patrick Reardon notes (here) that the Church remembers the descent Holy Spirit on a daily basis during the prayer at the Third Hour. Among these prayers is Psalm 50 which refers to the Holy Spirit three times. He writes regarding the first reference:
First, “Create in me a clean heart, O God; and renew the right Spirit within me.” This verse tells us that renewal in the Holy Spirit is inseparable from purity of heart. In those who are impure of heart there is no guidance of the Holy Spirit, no Spirit of wisdom, no Spirit of discernment, no fear of God.
It is imperative that the Holy Spirit not be confused with just any spirit that happens to speak to us. Indeed, most of us know our hearts well enough to suspect that most spirits that speak to us are not of God at all. And if our own hearts do not warn us of this danger, God’s Word does so. “Beloved, believe not every spirit, but try the spirits whether they are of God,” wrote St. John (1 John 4:1).
The Apostle John perceived, even in his own day, the peril of confusing the Holy Spirit with every manner of deception and mendacity. The Bible insists that there are many spirits in this world that have in mind to deceive the children of God. These spirits will usually tell us exactly what we want to hear, which is why we listen to them readily. We recall the admonition of the prophet Micaiah to King Ahab. He describes the evil spirit who boasts, “I will go forth, and I will be a lying spirit in the mouth of all his prophets” (1 Kings 22:22). And this lying spirit tells King Ahab exactly what he wants to hear.
We are properly warned in God’s Word about listening to those spirits who tell us what we want, those evil spirits who encourage us in the impurity of our hearts.
So we pray, “Create in me a clean heart, O God; and renew the right Spirit within me.” These two things are inseparable: purity of heart and the discernment of the right Spirit.