To what extent is the authenticity of the hadith: "The wise one, the wise one... for semen is the light of your eyes and the marrow of your shins," narrated from the Prophet, peace and blessings be upon him, after his return from battle? And does it have any origin?

We have not come across a hadith from the Prophet, peace and blessings be upon him, in which he says: "Semen is the light of your eyes and the marrow of your shins." However, this statement has been transmitted from some scholars.

As for the hadith: "Al-Kays, Al-Kays" (The prudent, the prudent), it is reported in the two Sahih collections and others. There has been disagreement regarding its explanation; it was said that it means seeking offspring, and it was said that it is an incitement to intercourse, and other interpretations were given. Among its explanations is that it means caution, or intellect, or gentleness and carefulness, and Ibn Hibban definitively stated that it refers to intercourse.