«بَابْ مَرْدُودْ شَر مَطْرُودْ»

The proverb praises precaution: sensible barriers and careful limits can prevent danger before it reaches a person, household, or undertaking. Its door is a figurative image for any effective safeguard, not only a physical door.

It favors acting early rather than waiting for harm to occur. What is securely guarded is less exposed to disruption, loss, or unwelcome intrusion, presenting caution as practical prevention.

Use it when approving a protective measure, such as securing access, setting firm boundaries, or taking precautions against a foreseeable problem. It frames caution as practical prevention rather than needless fear and can apply to safeguards beyond a literal door.