This piyyut of unknown authorship is certainly ancient, showing the lack of a rhyme scheme characteristic of the REALLY old piyyutim (see also Aleinu or El Adon). It is still found in some Ashkenazi and Teman maḥzorim, with many different mostly minor variants (which have been combined together somewhat eclectically into one text here). It is presented here along with an English translation attempting to preserve the Hebrew acrostic. Originally it was recited before the Ashrei leading into musaf, but perhaps for those who follow Ashkenazi customs a more appropriate location would be as an introduction to the Yizkor service on Shmini ‘Atzeret — which for those who don’t keep second-day yontef is the same day. It could also be adapted as part of the liturgy for the seventh of Adar, although the final verse (the old Western rite berakha for finishing a full Torah cycle) would have to be elided. . . .