In "Anthem for Doomed Youth," what sort of religious ceremony is taking place, and what details from the poem support your thoughts?
I'd call it a religious rite rather than a religious ceremony. Although written in the sonnet form, this poem is an elegy, or lament for the dead. Wilfred Owen wrote the poem out of his own experience of World War I. That was has been called "the war to end all wars"--and if only that were true. Before WWI, warfare seemed to follow a kind of structure, almost like a football game with each side lined up against the other. WWI introduced new horrors, with armored weapons, air raids, and chemical warfare.
The horrors of war dominate the first eight lines. We see men "die as cattle," in other words slaughtered. We hear the guns and bombs. Owen says that no church bells will toll for their funerals; instead there will be the bugle call. The only choirs that will accompany them to the afterlife are the "shrill, demented choirs of wailing shells."
In the final six lines we experience the distorted "funeral" that awaits these dead soldiers. No candles will be placed around their coffins. The only "window blinds" that will be drawn for them will be nightfall.
Visit the links below for more information.
In 'Anthem for Doomed Youth' by English world war one poet Wilfred Owen, a mournful tone is set for the 'religious ceremony' so we presume it is a funeral. The words 'each dusk a drawing down of blinds' set the mood - in some parts, curtains and blinds are drawn as a mark of respect for a coffin going by.
A mood of poignancy is evoked by the listing of fitting tributes the young fighters would never get. Every religious symbol listed makes the reader become more sorrowful as they realise there will be more casualties, more needless deaths. Instead of prayers, hasty orizons, or bells, candles and choirs - all the soldier lads will have is the ugly, monstrous noises, shrill and demented battle cries and roars as music instead. Owen uses language such as 'patter' not only to mimic the fire but to underline hypocrisy and superficiality in the battle campaign and propaganda - patter refers to superficial dialog (as in 'sales patter.')