This celebration on February 2, also known as Candlemas, marked the end of the Christmas season (not Epiphany as is often thought). It celebrates the presentation of the Christ Child at the Temple in Jerusalem in conjunction with the Purification of Mary.
No individual voice seems to own the chant melody in this motet, and, after the opening phrase, the chant is freely paraphrased throughout and difficult to identify. Nonetheless, it is a charming shorter piece with a very modal harmonic bent, perhaps meant to portray the age of Simeon.
Responsum accepit Simeon a Spiritu Sancto non visurum se mortem nisi videret Christum Domini.
Simeon had received a revelation from the Holy Spirit that he would not see death before he had seen the Lord’s Messiah.