Few people know what the Bishop Valentine did during his tenure, but the story of his martyrdom for Christianity has been passed down. According to a medieval story, Valentine was arrested during the reign of Roman Emperor Claudius II. The emperor appreciated the bishop's knowledge very much and hoped that he would give up his faith and live. As a result, Bishop Valentine persuaded the emperor to convert to Christianity, and he was finally sent to death row. Before being executed, Valentine performed a miracle and cured the jailer's daughter, You's eyes. The jailer's family converted to Christianity, so the story of the martyr Valentine spread.
Saint Valentine cured you, Leah's blind girl.
As for Baidu Encyclopedia and various websites, such as "Valentine died in a wedding ceremony for a lover", "Love between Valentine and a blind girl" and "Valentine's Day from Rome" are just the imagination of future generations, just trying to add some love factors to the death of St. Valentine. In fact, for a long time, Christians didn't think this saint had anything to do with love. Everyone pays attention to his miracle of curing blind girls, so St. Valentine is a medical saint in Slovenia, and some beekeepers especially worship him (probably hoping that St. Valentine will protect their eyes from bee stings). What the British pay attention to is that Valentine is kind to a girl, so in the imagination of the British in the Middle Ages, saints would give gifts to their children.
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In essence, this is a completely unknown saint, a festival with uncertain date. Is it entirely because of Cadbury, the famous chocolate manufacturer of 1868? Business lies fabricated by unsalable chocolate.