The story, according to James of Voragine.
Sequence by Adam of St. Victor:
Verbi bajulus fidelis,
Sacris disserit loquelis
Cum beata Virgine;
Verbum bonum et suave
Pandit intus in conclave
Et ex Eva format Ave,
Evae verso nomine.
Metum pellit, dat solamen:
"Nam per sacrum," inquit, "Flamen
"Et virtutis obumbramen
"Deo gravidaberis."
"Mater fiam," inquit ilia,
"Cujus vera sum ancilla;
"Salva tamen sint sigilla
"Pudoris, ut loqueris."
Consequenter, juxta pactum,
Adest Verbum caro factum:
Semper tamen est intactum
Puellare gremium.
Parem pariens ignorat,
Et, quam homo non deflorat,
Non torquetur, nec laborat,
Quando park filium.
Signum audis novitatis,
Crede solum, et est satis:
Non est tuae facultatis
Solvere corrigiam.
Grande signum et insigne
Est in rubo et in igne,
Ne appropiet indigne
Calceatus quispiam.
Virga sicca sine rore
Novo ritu, novo more,
Fructum protulit cum flore:
Sic et virgo peperit.
Benedictus talis fructus,
Fructus gaudii, non luctus!
Non erit Adam seductus
Si de hoc gustaverit.
Jesus noster, Jesus bonus,
Piae matris pium onus,
Cujus est in coelo thronus,
Ponitur in stabulo.
Qui sic est pro nobis natus,
Nostros deleat reatus,
Quia noster incolatus
Hic est in periculo. Amen.
Englished by Digby S. Wrangham:
Gabriel, sent from heaven to carry,
As Christ's faithful emissary,
Greetings to the Blessed Mary,
Sacred words with her rehearsed:
Good and sweet the word he taketh,
As he in her chamber speaketh,
And of "Eva" "Ave" maketh,
Having Eve's name thus reversed.
Comfort gives he, fear dispelling,
By the Holy Ghost's in-dwelling,
Thee the Highest's shadow veiling,
"Thou," saith he, "shalt bear the Lord!"
"Be it so," by her was spoken,
"To His handmaid by this token;
"Let my virgin seal unbroken
"Be, according to thy word!"
As that promise thus declareth,
The incarnate Word appeareth:
But the virgin ever shareth
Still intact virginity.
Such a birth no mother showeth;
She, whom mortal man ne'er knoweth,
Pain nor labour undergoeth,
When she bears her progeny.
Of a wonder new thou hearest:
Have but faith, 'twill then be clearest:
This shoe's latchet, if thou nearest,
Thou art powerless to untie.
Great the lesson is, none higher!
In the bush and in the fire;
With feet shod let none draw nigher.
Lest he come unworthily.
The dry rod, without a shower,
In new manner, through new power,
Fruit produced as well as flower:
So a maid hath borne a son!
Blessed be that fruit for ever,
Fruit of joy, of sorrow never!
Had he tasted its sweet savour,
Adam ne'er had been undone.
Jesus, gentle as none other.
Holy son of holy mother,
King of heaven, is, as our brother,
To a manger-cradle brought.
May He, thus for our salvation
Born, effect our guilt's purgation,
Seeing that our occupation
Of this earth with risk is fraught. Amen.