“Hiding your light under a bushel”
What it means
Concealing your talents or achievements.
Where it comes from
A bushel was eight gallons of dry goods, and the vessel that measured it was a wooden tub easily large enough to put over a lamp. The image only works if you know the container.
How sure are we?
From Tyndale’s 1526 translation of Matthew’s gospel, which chose bushel for a Greek word describing a dry measuring vessel. The unit was familiar to every English reader of the period.