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Trent did not eliminate any Sequence
Are there any sources that witness use of this sequence on Advent?
Full of might and bitter that day shall be, on which all things shall perish: what is seen in bodily form, the earth, and all the creatures that swim.
The gentle judge will draw near, to measure out punishment strictly, and he will judge the ages, he whom created all. The high column of heaven will begin to tremble at his nod. Oh memorable day, on which all things shall be laid open!
And what shall become of the scribe’s mark, what of the tablet, if the column of the sky shall begin to be so afraid? And what shall human beings feel, or earth’s creatures, if the hosts of the heavens shall begin to tremble so?
Oh you who as King lavish all things upon us – the eternal, the present – do not let us go into hell’s loathsome places, the dwellings of the devils – no, lead us to the angels’ realms! Amen.
Translation: Peter Dronke
As to the objection that the text is not a prayer for souls in Purgatory, several other texts of the Mass and Office for the Dead are not such.
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