All Souls Day
The All Souls Day and indeed the entire month of November (save the 1st) is dedicated to the deceased who have yet to be accepted into the kingdom of God. Read Maccabees 12:38-46 www.usccb.org/bible/2maccabees/12/38. Take note to verses 42 and 43. There you are reading words from a writing composed around 125 BC. What is clear is the similarity to the Catholic practice of remembering deceased relatives and friends. Prayers were offered for the victim warriors who may have have a atoned for a particular sin described in the suggested reading. The November 2nd date was established in the year 998 AD by Abbot St Odilo in the abbey of Cluny. Wikepedia offers a rather interesting account: another short read and means to understand the feast day.
The Church teaches that we have a duty to pray for the dead. The principal reason, again as the Church teaches, is to assist the dead who have not atoned sufficiently for the sins of life. Our prayers and sacrifices offered for these souls "speeds up" their departure date to heaven.
A visit to a church today where an Our Father, the Creed and the reception of Holy Communion as well as praying one Our Father and one Hail Mary for the intention of the Pope and participating in the Sacrament of Reconciliation seven day before or after the feast day are a practice that grants the deceased person entrance into heaven and the Beatific Vision.
This practice has diminished over the years. Why? Because it is another way of manifesting love for a deceased family member or friend. Not a bad deal for the person in Purgatory: your extra effort on this day will in effect release his/her soul from Purgatory and guarantee entrance into the Kingdom of God.
Indeed we have a unique grace that we can offer someone who may have need of that particular grace. I know this: when I die, I pray now that on All Souls Day at least one friend will perform this practice and open the gates of heaven for me.