Sian Mian Mir was a Sufi Muslim saint. He was close friends with Guru Arjan Dev Ji and went on to lay the foundation stone of Harmandir Sahib. The foundation stone was laid on January 13, 1588. This was key to the uniqueness of Harmandir Sahib as a space for all castes, creeds, and religions to be invited. Manvir Singh Ji describes on his blog "This was a symbolic act which demonstrated that a Sikh shouldn't look at a non-Sikh in terms of his/her laws but instead consider their values and value system. Baba Sai Mir Ji and other Sufi mystics close to the Guru Sahibs had the values and value system of Gurmat and Naam."