Since we do not know exactly what a belief in Purgatory meant in the devotions of North Italian Christians in the latter half of the thirteenth century, the best we can do is to point out that Purgatory (which the Second Vatican Council removed from dogma in the twentieth century) was a new and still imprecise idea . . .
This Sacred Council accepts with great devotion this venerable faith of our ancestors regarding this vital fellowship with our brethren who are in heavenly glory or who having died are still being purified; and it proposes again the decrees of the Second Council of Nicea,(20*) the Council of Florence (21*) and the Council of Trent.(22*)By confirming the decree of the Council of Trent on Purgatory, the fathers of the Second Vatican Council affirmed that
The Catholic Church, instructed by the Holy Spirit and in accordance with sacred Scripture and the ancient Tradition of the Fathers, has taught in the holy Councils and most recently in this ecumenical Council that there is a purgatory and that the souls detained there are helped by the acts of intercession (suffragia) of the faithful, and especially by the acceptable sacrifice of the altar.
Therefore this holy Council commands the bishops to strive diligently that the sound doctrine of purgatory, handed down by the Holy Fathers and the sacred Councils, be believed by the faithful and that it be adhered to, taught and preached everywhere. (Fifth Session, 1563)
The other "holy Councils" that taught about Purgatory are the Council of Lyon and the Council of Florence (Lumen Gentium cites and affirms the latter). It's important to note that both Trent and Vatican II warned against abuses of this doctrine in practice, but Vatican II confirmed the doctrine of Purgatory and the Catechism of the Catholic Church in paragraphs 1030 to 1032 also confirms Church teaching on prayers for the dead.
Why Le Goff, author of The Birth of Purgatory, made such an error is one question; why no editor (in the French original or English translation) corrected it or inserted a footnote explaining the error is another. Le Goff certainly provides no source for his statement (because there isn't any)! Lumen Gentium does not use the word "Purgatory"; did that omission confuse Le Goff? The Catechism should have cleared up his confusion.
That error just stunned me as I was reading the book, which I otherwise enjoyed because it is about two of my favorite religious subjects, the liturgical and sanctoral years--the cycle of seasons and feasts (fixed and movable) and saints' feast days. Archbishop Jacobus de Voragine divides the liturgical year into a cycle of salvation history as the "Temporale":
~The Time of Deviation (Adam to Moses--the Passion of Our Lord; the Purification and Annunciation)
~The Time of Renewal (Moses to the Nativity of Christ--Advent; Epiphany to Septuagesima/Lent, which includes the Octave of Easter)
~The Time of Reconciliation (Christmas to Epiphany and Easter to Pentecost)
~An hiatus between Christmas and Easter Season divided between the Times of Reconciliation and Pilgrimage
~The Time of Pilgrimage (Epiphany to Septuagesima during the Liturgical Calendar and our lives on earth)
Voragine also summarizes the Sanctorale: the feasts of martyrs and confessors, especially the martyrs of the Early Church, placing their feasts within the Temporale, so that Voragine presents, in Le Goff's opinion, a summa of time. The Christian lives in that time, sanctifying the Time of Pilgrimage by experiencing the liturgical year with the saints as models and intercessors. Thus the Church's calendar masters and renders our time on earth sacred.
On page 18, Le Goff describes Voragine's purpose to explain "the meaning of human time" to make "it possible to experience it" by demonstrating the "relations between the divine time of humanity that is real time and chronological time"--which is one reason as Le Goff says that Voragine is uncomfortable with the cycle of movable feasts in the Church's year. Those are the greatest feasts, after all, in the Times of Renewal and Reconciliation: Septuagesima/Lent, Easter, Ascension, Pentecost. Le Goff suggests that Voragine was either so attached to stability, a Divine attribute or "baffled by the complex calculations" used to determine the date of Easter and thereby all the movable feast before and after it. (p. 85)
Le Goff praises Voragine's story telling ability in the details about the lives of the saints and their miracles and good works; he emphasizes that Voragine is always interested in presenting historical facts (including dates) even though he gets them wrong; and that the Archbishop demonstrates an interest in the meaning of names (etymology) and numbers, particularly using numerical interpretative lists (three reasons for the season of Septuagesima; three characteristics of the Passion; four reasons for the significance of the Circumcision of Our Lord, etc), and his use, although sometimes incorrect, of major authorities and sources, St. Augustine, St. Ambrose, and others--even though, again, sometimes he confuses them (citing a sermon by Caesarius of Arles but ascribing it to St. Augustine, for example)--overall, Le Goff admires Voragine's achievement as an historian and as an important, complex, and subtle thirteenth century thinker (cf. p. 86).
There are two other sections that raised doubts in my mind that Le Goff was as complex and subtle a thinker he needed to be when dealing with certain distinctions he saw in Voragine's work:
Le Goff emphasizes that Voragine highlights this feast as the Annunciation of the Lord versus the Annunciation to the Virgin Mary. He suggests as a possible hypothesis that the "Dominican Order's hostility in the thirteenth century toward the doctrine of the Immaculate Conception of Mary" is behind this (for that time*) unique view of this feast. (p. 95) But even St. Thomas Aquinas in his Summa, Question 27, Article 1 accepts the sinlessness of the Mother of God, sanctified in her mother's womb, if not at the moment of conception:On the contrary, The Church celebrates the feast of our Lady's Nativity. Now the Church does not celebrate feasts except of those who are holy. Therefore even in her birth the Blessed Virgin was holy. Therefore she was sanctified in the womb.
Moreover, it is to be observed that it was granted, by way of privilege, to others, to be sanctified in the womb; for instance, to Jeremias, to whom it was said (Jeremiah 1:5): "Before thou camest forth out of the womb, I sanctified thee"; and again, to John the Baptist, of whom it is written (Luke 1:15): "He shall be filled with the Holy Ghost even from his mother's womb." It is therefore with reason that we believe the Blessed Virgin to have been sanctified before her birth from the womb.
Therefore, I don't think that Archbishop Jacobus de Voragine, OP emphasized the Annunciation of the Lord above the Annunciation to Mary because of opposition to her Immaculate Conception, since the leading Dominican theologian accepted belief in her sinlessness before her birth from the womb. Le Goff provides as a better explanation that Voragine wanted to emphasize the Incarnation of Jesus as the entry of God into human time, sanctifying it, because "Christ incarnate is truly the center of time." (p. 95)
The whole debate about the Immaculate Conception of the Blessed Virgin Mary began with Eadmer, the monk of Christ Church in Canterbury and friend of Saint Anselm of Canterbury with the publication of the former's De Conceptione sanctae Mariae
*In the revisions of the Roman Missal and Calendar in 1970, the name of the feast was changed from The Annunciation of the Blessed Virgin Mary (as it is called in the Roman Missal of 1962) to The Annunciation of Our Lord.
2. The Birth of the Virgin Mary
It seemed to me that Le Goff confused the births of Mary and St. John the Baptist. Le Goff notes that Voragine considers the background in the Old Testament of mothers giving birth to sons long after their childbearing years: Sarah and her son Isaac; Manoah's wife and Samson; Hannah and her son Samuel. Then he says: "Thus Elizabeth's birth to a mother who had long been sterile was not exceptional." And he repeats: "Elizabeth was not unique as the daughter of a long barren mother . . . she belongs to a category with Old Testament antecedents." (p. 123) Doesn't he mean "Mary's birth to a mother [St. Anne according to the Protoevangelicum of James] who had long been sterile"? and "Mary was not unique as the daughter of a long barren mother"?
Elizabeth was barren until she and Zechariah conceived St. John the Baptist, as announced to Zechariah by Gabriel in the first chapter of the Gospel according to St. Luke. She was the mother of a son conceived late in life (John) as St. Anne was the mother of a daughter (Mary) conceived late in life. So I'm not sure how Le Goff confused these later pregnancies of Elizabeth and Anne. It's certainly not in The Golden Legend, which does rely on the Protoevangelicum and St. Bede, as Le Goff notes.
Again, I wonder if some copy-editor along the way shouldn't have corrected this confusion; I don't have access to the original French edition; surely this is not an error in translation?!?
In spite of these three anomalies (the status of Purgatory as Catholic doctrine; the debated teaching about the Immaculate Conception and the title of the feast of the Annunciation; and the confusion about the birth of the Blessed Virgin Mary), I enjoyed this book very much.
Le Goff sees a fellow historian doing his best to get it right in Jacobus de Voragine and The Golden Legend. As he states on page 115:
it seems to me that he [Voragine] sees in time, which is a gift from God, above all an instrument for explaining the march of humanity and a means whereby man, guided by the lessons of liturgical time and the exemplary character of the time of the saints, may achieve perfection.
Neither Voragine, nor Le Goff, nor this reviewer has achieved perfection, but I recommend this book: Le Goff tried to get it right in expressing his admiration for Voragine in his Summa on time, liturgical, sanctoral, and during the pilgrimage of life until the end of the world. He demonstrates how the author of The Golden Legend tried to help his fellow Christians live in the real time, the time that matters, not just the chronological time of day to day life, but with eternal life in mind as revealed by the Catholic Church in her liturgy, history, and people.
After all, we don't know how long the Time of Pilgrimage will last for any of us or for the world!
Image credit (public domain): the cover of In Search of Sacred Time features a detail from Lorenzo di Credi's Annunciation; here is an image of the entire painting.