The Book of Common Prayer gives a very good description of the "liturgy for the dead":

"The liturgy for the dead is an Easter liturgy. It finds all its meaning in the resurrection. Because Jesus was raised from the dead, we, too, shall be raised.

The liturgy, therefore, is characterized by joy, in the certainty that 'neither death, nor life, nor angels, nor principalities, nor things present, nor things to come, nor powers, nor height, nor depth, nor anythig else in all creation, will be able us from the love of God in Christ Jesus our Lord.'

This joy, however, does not make human grief unchristian. The very love we have for each other in Christ brings deep sorrow when we are parted by death. Jesus himself wept at the grave of his friend. So, while we rejoice that one we love has entered into the nearer presence of our Lord, we sorrow in sympathy with those who mourn."