This is the will of the one who sent me: that I should not lose anything of what he gave me, but that I should raise it on the last day. The Church, after celebrating the feast of All Saints, today prays for the faithful departed. That the commemoration of the faithful departed immediately follows the celebration of those who have attained sanctity is no mere coincidence. The two celebrations are connected and can, as a matter of fact, be seen as a celebration of the same event. While yesterday’s celebration focused on those who have attained sanctity and are already rejoicing with God and the angels in heaven, today’s focus is on those who have died but are yet to attain the blessed status. Such souls have traditionally been understood by the Church to be in a state of purification (purgatory) as they await that time when they will join God in blessed happiness. The designation of today’s commemoration (all the faithful departed) is an admission that God is the only judge of the living and the dead, and that where the souls of the departed end solely rests with God. And so when today the Church remembers them in prayer, she is not only fulfilling the great commandment of charity toward the dead, but is also reiterating the belief that communion with God is the final end of creation. The creative process only gets to be complete when everything that is from the Father returns to the Father. 
Although the will of God is that we attain communion with God here on earth and in the life after, men and women, because of free will, strive for emancipation from God’s will in order to follow their own wills. It is a temptation with which men and women struggle in the course of their lives. While some are able to overcome the struggle through their cooperation with God’s grace, there are those who let the temptation get the best of them and they end up separating themselves from God. Their living outside God’s grace makes it impossible for them to live a life that is in conformity to the will of God (“the will of God is that all men and women are saved by coming to the knowledge of the truth” cf. 1 Timothy 2:4). And sometimes, they end up departing this world in such ungraced condition. It is this group that the Church remembers and for whom she prays today. She does so in the belief that God’s mercy and love is greater than humanity’s transgressions, and that God’s plan for his creation can never be thwarted by our sins. For God says that even though our sins might be as red as crimson, he can do away with them and make us as white as snow (cf. Isaiah 1:18).
When the Church prays for the faithful departed, she is emboldened by Jesus’ statement that the Father’s will for him is that none of his brothers and sisters should be lost (cf. John 6:37-40). Jesus as the Word incarnate assumed human nature so that men and women can once again stand erect and stare into God’s blessed face (seeing God face to face). This mission of Jesus is not complete until every created reality comes into communion with their Creator. Through the Church’s prayers, suffrages and penances, those who are yet to experience the blessed peace that is only realized when one sees God face to face are helped to attain this.