Pentecost is a Christian holiday which takes place on the 49th day after Easter. It commemorates the descent of the Holy Spirit upon the Apostles of Jesus while they were in Jerusalem celebrating the Feast of Weeks, as described in the Acts of the Apostles. Many churches, including the Roman Catholic Church and Eastern Orthodox Church, believe the Holy Spirit descended upon Mary, the mother of Jesus, at the same time, as also recorded in the Acts of the Apostles.