It is read that the decollation of Saint John Baptist was established for four causes, like as it is found in the Book of Office. First, for his decollation; secondly, for the burning and gathering together of his bones; thirdly, for the invention and finding of his head; and fourthly, for the translation of his finger and dedication of the Church. And after some people this feast is named diversely, that is to say, decollation, collection, invention, and dedication.
Fourthly, this feast was hallowed for the translation of his finger and the dedication of his church. For his finger with which he showed our Lord remained unburnt though the rest of his body was consumed by the flames. The finger was found by some monks and, as it says in the Historia Scholastica, the finger came into the hands of Saint Thecla who brought it over the mountain, and set it in the church of Saint Martin [...] And Gobert saith that a much devout lady towards Saint John was in France, which much prayed to our Lord that he should give to her some relics of the said Saint John, and when she saw that it profited not in praying to God, she began to take affiance in God, and avowed that she would fast and never eat meat till she had of him some relic. And when she had fasted certain days she saw upon the table tofore her a finger of marvellous whiteness, and she received with great joy that gift of God. Then after, came thither three bishops, and each of them would have part of the finger. Then by the grace of God the finger dropped three drops of blood upon a cloth by which they knew that each of them had deserved to have a drop. And then Theodolina, queen of the Lombards, founded at Modena, beside Milan, a noble church in the honour of Saint John Baptist.
And like as Paul witnesseth in the History of Lombards: And the time passed unto Constance the emperor which would have taken Italy from the Lombards, and he demanded of a holy man which had a spirit of prophecy, how he should do with the battle which he had enterprised. And that man was all night in prayer and came to the emperor and answered to him and said: The queen hath do made a church of Saint John Baptist and prayeth continually for the Lombards, and therefore thou mayst not surmount them, but the time shall come that that place shall be despised, and then they shall be overcome. Which was accomplished in the time of Charlemagne.
– Jacobus de Voragine, Legenda Aurea