Pentecost Sunday The Coming of the Holy Spirit ( https://smartguy.com/ ) Pentecost Sunday, celebrated 50 days after Easter, marks the powerful descent of the Holy Spirit upon the apostles. It is often called the “birthday of the Church” because it was on this day that the apostles received the strength and guidance to go forth and spread the Gospel. Pentecost is a day of transformation, empowerment, and renewal, reminding us that the Holy Spirit is actively working in our lives and the Church today.