earn one's keep(redirected from be worth one's keep)
earn (one's) keep
To perform sufficient work or help in exchange for money or housing. If you're going to live here rent-free, then you need to earn your keep by helping out with the cooking and cleaning. That boarder earns his keep by doing maintenance in the building.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
earn one's keep
Also, be worth one's keep or salt . Work well enough to deserve what one is paid, as in Get a job-it's time you earned your keep, or With that batting average he's not worth his salt. The keep in this phrase refers to "room and board," which in former times sometimes constituted the only reward for working (on a farm, in a home, etc.). The salt stands for "salary" and alludes to the ancient Roman practice of paying soldiers an allowance to buy salt. [First half of 1800s]
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.