tell tales out of school, to

tell tales out of school

To share secrets, often knowing that doing so will cause problems for someone else. Here's a tip: don't tell tales out of school about your co-workers if you want to have any friends here.
See also: of, out, school, tales, tell

tell tales out of school

to tell secrets or spread rumors. I wish that John would keep quiet. He's telling tales out of school again. If you tell tales out of school a lot, people won't know when to believe you.
See also: of, out, school, tales, tell

tell ˌtales out of ˈschool

talk about the private affairs of a group or an organization to people who do not belong to it: I shouldn’t tell tales out of school, but my company is in serious trouble.
See also: of, out, school, tales, tell

tell tales out of school, to

To reveal secrets; to talk out of turn. The earliest appearance of this expression in print occurred in William Tindale’s The Practyse of Prelates (1530): “What cometh once in may never out, for fear of telling tales out of school.” Presumably it first applied to children gossiping about what they heard at school, but it soon was used figuratively. It is now on the verge of obsolescence. However, just plain to tell tales, meaning to lie, survives.
See also: of, out, tales, tell