Having found online the Vitæ SS. Joannis de Mattha, et Felicis de Valois, &c., by that learnèd Franciscan Francis a S. Augustino Macedo, published at Rome in 1660, I give both his splendid Latin description of the celestial Matins celebrated by Our Lady and all the company of heaven together with St Felix, and my poor rendering of what turned out to be a very difficult piece of prose:
Ædificato jam in Cervo frigido amplo Cœnobio, & frequenter habitato à fratribus, & noctes matutinis psalmis resonante, accidit, ut pulsantis negligentia æra Campanæ ea ipsa sacratiori nocte natalium Deiparæ anniversario pervigilio, penitus silerent. Quamquàm hoc non negligentiæ, sed providentiæ assignandum videretur. Qùi enim possent ea nocte fratres vigiliis assueti, tam profundè sopiri, quam Religio, vel insuetis reddit insomnem? Vigilabat de more Felix, & quòd horas prævenire solitus, in chorum prior venerat. Meliores ibi psaltes socios habuit. Deipara Virgo è cœlo lapsa secum adduxerat cælites; ac ut habitus loco responderet, & ne concentus vocum à conspectu oculorum discreparet, cùm Virgo ipsa, tùm сomitatus solemnem Familiæ Crucem gestabat. Eminebat Deipara, & nitida luce perfusa vincebat tenebras. Et quasi expectasset, dum veniret Felix siluit, ubi is adfuit, voce suavissima præcìnuit Antiphonas. Secuti sunt Angeli Sanctis intermixti. Divisi in choros alternis canentes Matutinum cum Felice officium persolverunt. Fuit hoc futuræ mortis præsagium; cantus ille Cygnæum quiddam præseferebat.
([Pars II.] "Vita S. Felicis de Valois", Cap. VIII., p. 104f.)
An ample monastery having been built at Cerfroid, both oft dwelt in by the brethren, and by nights having resounded with matins psalms, it happened, that by forgetfulness of the ringers the brass bell thereof, on that more sacred night vigil on the anniversary of the birth of the Mother of God, was wholly silent. Although it may be seen that this was not out of negligence, but assigned by providence. For wherefrom were the brethren, accustomed to vigils, able that night both deeply to be lulled to sleep, and by Religion, especially as they were accustomed to offer up sleeplessness? Felix by custom kept vigil, and because he was wont to anticipate the hours, in choir first he worshipped. There he had sweeter companion psalmists. The Virgin Mother of God from heaven descended, with her she brought citizens of heaven; and that she correspond to the habit of the place, and lest the harmony of voices be different from what the eyes consider, as with the Virgin herself, so the solemn company wore the Cross of the Order. The Mother of God became visible, and pouring forth brilliant light conquered the darkness. And as if expected, when having come Felix was silent, where she was present, with a most sweet voice she sang the antiphons. Angels intermixed with saints followed. Singing, divided into alternate choirs, with Felix they discharged the office of Matins. This was for him a presage of his impending death; it was as it were his swansong.
As mentioned below, this visitation, a foretaste of that perpetual canticle of praise sung before God and the Lamb, was vouchsafed St Felix of Valois within two months of his death: it was indeed his earthly swansong, but only as it were a clearing of his throat ere he joined for ever the choirs above.
May this consoling tale inspire us in our prayers, particularly when joining in the Prayer of the Church in her sacred round of liturgy, that, as Tertullian said, we may fit ourselves now for what we hope will be our endless employ hereafter.