toe the line
To adhere to the rules of something. (Often misspelled as "tow the line.") From now on, I plan to toe the line and do exactly what Gram tells me, to avoid getting in any more trouble. I expect you to toe the line at all times if you want to remain at this firm, Jonathan.
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.
1. To adhere to doctrines or rules conscientiously; conform.
2. Sports & Games To touch a mark or line with the toe or hands in readiness for the start of a race or competition.
See also: toe
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.