Be cautious when dealing with strangers; Use henna as an identification tool for women; Show respect and consideration towards others even in small matters; Follow advice of Prophet Muhammad SAW .

This hadith is about the Prophet Muhammad's caution when accepting letters from strangers. He did not know whether it was from a man or a woman, so he asked the woman if she was indeed female. When she confirmed that she was, he advised her to dye her nails with henna in order for people to recognize that she is a woman. This hadith teaches us that we should be careful when dealing with strangers and also encourages women to use henna as an identification tool. It also shows us how considerate and respectful the Prophet Muhammad was towards women even in such small matters like this one.