The horns are based on Jerome's translation of the Hebrew word קָרַן (qaran) in Exodus 34:29 which means to send out rays or shine, and is related to the root word for horn (compare e.g. Genesis 22:13 where Abraham's ram for sacrifice is caught by its בְּקַרְנָיו (qeren)). Jerome used a similarly flexible word (cornuta), but the ambiguity lead to some interesting artistic interpretations.
English doesn't exactly have a linguistic relationship between radiant and horns, so it is "fixed" in every translation except the Douay-Rheims which is a direct Vulgate translation rather than referencing the Hebrew text.
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