I never knew what a bushel actually was. I had a vague idea it was a pile of grain or something. Apparently it's a unit of dry weight, or a woven basket of that size.
I also note, the meaning seems to be about the metaphor of hiding a physical lamp under a basket, not of hiding radiated light under a basket, though they have the same meaning.
The version in Mark isn't very clear to me -- it's clear we're not supposed to hide something, but I can't easily tell what. Our awesome Jesus-following-ness is one interpretation, but it could almost equally well be "don't hide things you're ashamed of, they'll come out anyway, own up to them now"
Whereas Matthew explicitly says something close to the modern colloquial meaning "let your light shine before others, so that they may see your good works and give glory to your Father who is in heaven."
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