Bishop Alfred Schlert, of the Diocese of Allentown, celebrated the beginning of the Easter season, which lasts until Pentecost, by tweeting about the glory of the Resurrection.

“Alleluia! He has Risen! Alleluia!” Schlert tweeted. “Blessed Easter to all the faithful of the Diocese of Allentown! We live in the glory of the Resurrection. He has Risen as He said, Alleluia!” 

The Easter season is the most important season of the liturgical calendar, spanning 50 days from Easter Sunday until Pentecost, the U.S. Conference of Catholic Bishops (USCCB) says. 

The season is called Easter for a reason. The word Easter comes from the Old English and means "East." As the sun rises in the east and lights the world with warmth and hope, the risen Christ is the Light of the world. Hence the name for the season, the USCCB explains.

Fifty days after Jesus' resurrection, and around 10 days after his ascension into heaven, Jesus' followers gathered inside of a room. Christianity.com describes the scene, saying there was a sound, as if a gust of wind had rushed into the room, and tongues of fire appeared over the heads of Jesus' followers. With that, the Holy Spirit filled them, and they began to speak in tongues. A crowd gathered around them, and everyone in the crowd could hear Jesus' followers speaking in his native language. Peter preached to the crowd and 3,000 people converted to Christianity that day. 

This year, the Ascension of the Lord will be on May 29, the USCCB says. The Gospel reading set for that day describes Jesus leading his disciples outside of Jerusalem. He blessed them, and then he "was taken up to heaven." His disciples returned to the city and spent their time praising God.