To hold back troops and not take action; to bide one's time; to wait for an opportune moment before acting; (figuratively) to delay taking action or starting a project.
Era:
Ancient
Frequency:
Story:
The ancestor of the Zhao state's ruler was preparing to attack the state of Wei and dispatched Shi Mo to gather information there.
Shi Mo returned only after a year, which angered Zhao Jianzi, who asked, "Why did you take so long to come back?"
Shi Mo replied, "I conducted a thorough investigation of the situation in Wei, which is why it took a while. Presently, the ruler of Wei is very enlightened, and he is assisted by many virtuous talents; the state is governed exceptionally well. It is not yet the opportune moment to attack Wei, and I advise you not to act rashly."
Zhao Jianzi found Shi Mo's counsel sound, so he decided to 'keep his troops stationary' (按兵不动) and awaited a more favorable time.
This idiom originally referred to holding back one's forces temporarily and refraining from action, awaiting the right opportunity. It now also metaphorically describes delaying action after being given a task.