This is just a sequence from the film by Carl Theodor Dreyer, and not the official trailer. But it really does not matter which part of the film is shown because this is one of the most beautiful films I have seen.
I must say that Richard Einhorn’s composition Voices of Light made the film even more powerful. Dryer did not necessarily even include a score for the film but I think it is hard to deny how greatly the film and the composition compliment each other.
I strongly recommend this beautiful piece of art!