He Is Risen! Easter celebration

But at daybreak on the first day of the week they took the spices they had prepared and went to the tomb. They found the stone rolled away from the tomb; but when they entered, they did not find the body of the Lord Jesus. While they were puzzling over this, behold, two men in dazzling garments appeared to them. They were terrified and bowed their faces to the ground. They said to them, “Why do you seek the living one among the dead? He is not here, but he has been raised. Remember what he said to you while he was still in Galilee that the Son of Man must be handed over to sinners and be crucified, and rise on the third day.” And they remembered his words. Then they returned from the tomb and announced all these things to the eleven and to all the others. The women were Mary Magdalene, Joanna, and Mary the mother of James; the others who accompanied them also told this to the apostles, but their story seemed like nonsense and they did not believe them. But Peter got up and ran to the tomb, bent down, and saw the burial cloths alone; then he went home amazed at what had happened. (from Luke 24)
Easter (also called the Pasch or Pascha) is the Christian festival and holiday celebrating the resurrection of Jesus Christ on the third day after his crucifixion at Calvary as described in the New Testament. Easter is the culmination of the Passion of Christ, preceded by Lent, a forty-day period of fasting, prayer, and penance. The last week of Lent is called Holy Week, and it contains the days of the Easter Triduum, including Maundy Thursday (also known as Holy Thursday), commemorating the Last Supper and its preceding foot washing, as well as Good Friday, commemorating the crucifixion and death of Jesus. Easter is followed by a fifty-day period called Eastertide or the Easter Season, ending with Pentecost Sunday. Easter is a moveable feast, meaning it is not fixed in relation to the civil calendar. The First Council of Nicaea (325) established the date of Easter as the first Sunday after the full moon (the Paschal Full Moon) following the March equinox.