From the earliest days of the church, the observance of Easter has always included a period of spiritual preparation beforehand. In the second century, Iraneus wrote of a period of two or three days of reflection. It is believed the Council of Nicea in 325 A.D. first discussed a 40-day period, noting the 40 days Jesus spent in the desert preparing for ministry.
Around the year 600, Pope Gregory the Great set the period of Lent as 46 days – 40 days not counting Sundays, which were already celebrations of the Resurrection – which meant the season would commence on a Wednesday.
Observations of Lent differ. The theme is always one of penance and prayer, with a focus on spiritual discipline that often includes fasting. This is a particular emphasis of the Roman Catholic church, which has guidelines for fasting during Lent. In the Eastern Orthodox church, Lent begins on Clean Monday, 55 days before eastern Easter. That’s 40 days, not counting the Saturdays or the Sundays.
In every tradition, the spiritual focus sharpens in Holy Week, the final week before Easter, in which Christians recall the events leading to Christ’s betrayal, trial, crucifixion, death and Resurrection. The “Easter season” follows and lasts 50 days, ending on Pentecost Sunday, which this year falls on June 4.