The annual Pentecost tradition (today!) at Rome's Pantheon is a moment of extraordinary beauty. It occurs every year on the seventh Sunday after Easter. At noon, after the Holy Mass, thousands of rose petals are dropped through the oculus of the mighty dome. As the petals fall, a choir sings "Veni Sancte Spiritus," known as the Golden Sequence, a masterpiece of sacred Latin poetry. This is to celebrate the descent of the Holy Spirit on the Virgin Mary and the Apostles. The rose petal ritual likely dates back to 607 AD when the pagan temple became a Christian church.