How Are the 40 Days of Lent Calculated?

Why Sundays don't count during Lent

The question: the period of prayer and fasting in preparation for Easter is 40 days long, but there are 46 days between Ash Wednesday, the first day of Lent in the Roman Catholic Liturgical calendar, and Easter. So how are the 40 days of Lent calculated?

The answer takes us back to the earliest days of the Church. Christ's original disciples, who were Jewish, grew up with the idea that the Sabbath - the day of worship and rest - was Saturday, the seventh day of the week, since the account of creation in Genesis says that God rested on the seventh day.

Since all Sundays - and not simply Easter Sunday - were days to celebrate Christ's Resurrection, Christians were forbidden to fast and do other forms of penance on those days. Therefore, when the Church expanded the period of fasting and prayer in preparation for Easter from a few days to 40 days (to mirror Christ's fasting in the desert, before He began his public ministry), Sundays could not be included in the count.

Thus, in order for Lent to include 40 days on which fasting could occur, it had to be expanded to six full weeks (with six days of fasting in each week) plus four extra days - Ash Wednesday and the Thursday, Friday, and Saturday that follow it. Six times six is thirty-six, plus four equals forty. And that's how we arrive at the 40 days of Lent!