Meaning:
This idiom means that if you get involved in something dishonest or shady, you will inevitably get your hands dirty. It signifies the inevitable consequences of engaging in corrupt or unethical activities. You will be implicated in the wrongdoings and face negative repercussions, even if you only play a minor role.
Example:
* "जो लोग भ्रष्टाचार में शामिल होते हैं, वे कोयले की दलाली में हाथ काले करने वाले होते हैं।" (Those who engage in corruption are like those who get their hands dirty in the brokerage of coal.)
In essence, the idiom warns against engaging in activities that can tarnish your reputation and lead to unwanted consequences.