From a friend priest in regard to the chant in the video.
I saw that YouTube clip. Although it is the Exsultet chant of the Easter Vigil, the whole thing is taken out of context. The chant is very ancient–more than 100 years, maybe back to St. Augustune–and refers to Jesus Christ as the Light Bearer who knows no sunset after His Resurrection. There is no blog to offer comment after the clip concludes. I repeat: the Catholic Church has been using this chant over 1000 years, and it refers to Jesus Christ–not Satan.