The day before the All Souls' Day, all People of different church denominations especially the Catholic Church, observe All Saint's Day, a widespread practice of Christians since the earliest days of the Roman Catholic church.
This is a celebration on which the Church solemnly commemorate and honours all the known and nameless saints and martyrs who lived and died for God and have helped in shaping the Christian faith across the world.
According to some sources, the idea for All Saints' Day goes back to the fourth century when the Greek Christians kept a festival on the first Sunday after Pentecost in honour of all martyrs and saints. It was introduced in Rome on May 13, 610 as the “Feast of All Holy Martyrs” by Pope Bonifice IV. In his pontificate, Gregory III (731-741) changed the date and the name of the feast to November 1 and renamed the feast to All Saints/Hallows Day.
Halloween is actually an Old English word which literally means All Hallows Eve and traditionally celebrated on the eve of the 31st of October. Hallows was a word that referred to the Saints. They were the "hallowed or blessed ones", in the same sense that we say "Hallowed be Thy name" in the Lord's prayer.
Who are the Saints?
God declares everyone who has been baptized and believes the promise of the gospel to be justified, holy, and blameless. The communion of saints therefore includes both those still living on earth and those who have died in the faith and are now living in heaven.On this day we glorify God not just for the faithfulness of all the saints, but most of all for His faithfulness to the saints. This feast reminds us that it is only by the perfect life and saving death of Jesus Christ that Christians are made saints in the sight of God.