The article explores Vladimir Solov’ev’s philosophical and theological engagement with Islam, analyzing his dual perspective as both a critic and admirer of the faith. Solov’ev, a prominent 19th-century Russian philosopher, viewed Islam through the lens of his concept of "All-Unity" (vseedinstvo), which seeks to reconcile opposing forces in religion and history. His early critique in Three Forces (1877) presents Islam as a monolithic system suppressing individuality, contrasting it with Western individualism and Slavic spiritual synthesis. Later, in Muhammad: His Life and Religious Teaching (1896), Solov’ev offers a nuanced portrayal of the Prophet, acknowledging Islam’s monotheistic rigor and moral framework while critiquing its lack of progressive ideals. The article highlights Solov’ev’s mystical Sophia visions, which underpinned his belief in a transcendent "Religion of the Holy Spirit" surpassing all singular faiths. Despite his eschatological focus on Christian unity, Solov’ev’s late writings suggest an inclusive spiritual universalism, though he remained silent on Islam’s role in the end times.