Saturday, April 19 is Holy Saturday, the final day of Lent and Holy Week, which is a solemn day preceding the joyous Easter holiday. 

Holy Saturday is a quiet day when Christians commemorate the death of Christ and anticipate his resurrection. 

Holy Saturday, also known as the Easter Vigil, used to be a day for fasting. According to the Catholic Encyclopedia, "In the early Church, this was the only Saturday on which fasting was permitted."

Fasting is a sign of penance, but Christians believe that on Good Friday, the day before Holy Saturday, Christ paid with his life for the sins of humanity. Therefore, for many centuries, Christians actually regarded both Holy Saturday and Easter Sunday as days on which fasting was forbidden. There is still fasting in the Eastern Catholic and Eastern Orthodox Churches, but their fasting is lessened on Saturdays and Sundays. 

But in the second century, Christians began to observe a complete fast for 40 hours before Easter, which meant Holy Saturday was a day of fasting. 

Fasting and abstinence was still practiced on Holy Saturday to remind Christians of the sorrowful nature of the day until rules were revised in 1969. Fasting is no longer required, but some devout Christians still practice the Holy Saturday fast to observe the solemn day. 

There is no Mass on Holy Saturday. Easter Vigil Mass takes place after sundown on Holy Saturday, which is considered to take place on Easter because each day begins at sundown on the previous day in the liturgical calendar. 

On Holy Saturday, the Eucharist is given to those who are in danger of death to "prepare their souls."

In the early Church, Christians gathered on the afternoon of Holy Saturday to pray and confer Baptism to "catcheumens," or converts to Christianity who had spend Lent preparing to be received into the Church. At dawn on Easter Sunday, the Alleluia was sung, and the newly baptized broke their 40-hour fast by receiving communion. 

Beginning around the 8th century, Easter Vigil began to be performed on Holy Saturday morning. Holy Saturday, which was originally a day of mourning for the crucified Christ, then became an anticipation of Easter Vigil.

Holy Week was then reformed in 1956, and the ceremonies were returned to the Easter Vigil itself, meaning Mass is celebrated after sundown on Holy Saturday.