لَا يُلْدَغُ الْمُؤْمِنُ مِنْ جُحْرٍ وَاحِدٍ مَرَّتَيْنِ
A believer is not stung twice from the same hole.
Source: البخاري ومسلم
يُلْدَغُ (“is stung”) is a passive present-tense verb. الْمُؤْمِنُ is its passive subject; مِنْ جُحْرٍ وَاحِدٍ means “from one hole,” and مَرَّتَيْنِ means “twice.”
The image teaches a believer to learn from harmful experience. Rather than being repeatedly deceived by the same method, one should identify what went wrong and take reasonable precautions.