mend one's ways

mend (one's) ways

To start behaving in a different, usually preferable, way. After I got in yet another fight at school, the headmaster told me that I had to mend my ways or else I'd be expelled. No matter how old you are, there is still time to mend your ways.
See also: mend, way

mend one's ways

Improve one's behavior, as in Threatened with suspension, Jerry promised to mend his ways. This expression, transferring a repair of clothes to one of character, was first recorded in 1868, but 150 or so years earlier it had appeared as mend one's manners.
See also: mend, way