Khidr, which is originally al-Khidr, is a man mentioned in Surat al-Kahf (chapter 18 of the Quran). The name itself is not mentioned in the Quran, but it is mentioned in Sahih al-Bukhari in a saying of Prophet Muhammad, peace and blessings of Allah upon him (Sahih al-Bukhari / Prophets / 3221). The saying mentions that the name al-Khidr, which etymologically related to “green”, “greenness”, came from the fact that wherever he stood on the ground, the ground would become green (with plants).