sing the same tune

sing the same tune

To have the same understanding of something as someone else; to say the same things about something as other people, especially in public. I think we should have a meeting with everyone who's involved in the project. That way we can all be singing the same tune before we begin. Make sure everyone the campaign is singing the same tune before we release any kind of statement to the press.
See also: same, sing, tune
References in classic literature ?
The nightingales in the forests about here all sing the same tune, and in the same key of (E flat).