The feast expresses the doctrine of the communion of saints: the conviction that the church on earth, the dead being purified, and the saints in glory form one body, able to pray for one another. On this reading the saints are held up both as examples and as intercessors, and the feast is one of confidence rather than mourning. In much of the Catholic world it is a holy day of obligation and a public holiday.
It is followed on 2 November by All Souls' Day, on which the faithful pray for all the dead, and the two days are often taken together as a single commemoration of the departed. The Reformation split the tradition here: many Protestant churches retained All Saints as a celebration of the whole people of God but rejected prayer for the dead and the invocation of saints, so that in Lutheran and Anglican use the day became, in part, a remembrance of all faithful Christians who have died. The popular customs of the eve, Halloween, are treated under their own entry.