Many Christians affirm the observance of Lent, a season of some forty days of fasting, penance, prayer, and almsgiving in preparation for Easter, recalling Christ's forty days of fasting in the wilderness. In the Western churches it begins on Ash Wednesday, when many receive ashes on the forehead with words recalling human mortality, drawn from Genesis, that one is dust and to dust one shall return; the Eastern churches keep a Great Fast of their own reckoning, beginning on what is called Clean Monday rather than a Wednesday, and calculated somewhat differently from the Western season.
The forty-day length was not fixed from the start. The earliest evidence for a pre-Easter fast, from the second century, points to a much shorter preparation, in some places apparently just a day or two immediately before the Easter vigil, and the extended forty-day period seems to have developed gradually over the following two centuries, becoming standard by roughly the fourth century, an era in which the season also became closely tied to the final preparation of catechumens awaiting baptism at Easter itself, so that Lent's penitential character and its role as baptismal preparation grew up together rather than separately.