His statement, “an odd number of times,” means three times in each eye.
They said: It is recommended to apply ithmid (antimony kohl) every night. It is a type of kohl that is highly beneficial for the eyes. Whoever wishes to learn more about it should read Zād al-Maʿād (1) by Ibn al-Qayyim, may Allah have mercy on him. It is among the best types of kohl for strengthening one’s eyesight.
It is said that Zarqāʾ al-Yamāmah could see a distance of three days’ travel with the naked eye. When she was killed, they examined her eye and found that its blood vessels were almost filled with ithmid (antimony kohl) (2).
As for applying kohl to beautify the eye, is it prescribed for men, or only for women?
The apparent view is that it is prescribed only for women. A man has no need to beautify his eyes.
It may be said, however, that it is also prescribed for men, because when the Prophet, peace and blessings be upon him, was asked about a person who likes his sandals to be fine and his garment to be fine, he said: “Indeed, Allah is Beautiful and loves beauty” (3).
It may also be said that if a man has a defect in his eye for which he needs to apply kohl, then it is prescribed for him; otherwise, it is not prescribed (4).