The Cloud of Unknowing is an anonymous work of Christian mysticism written in Middle English in the latter half of the 14th century. The text is a spiritual guide on contemplative prayer. The underlying message of this work suggests that the way to know God is to abandon consideration of God's particular activities and attributes, and be courageous enough to surrender one's mind and ego to the realm of "unknowing", at which point one may begin to glimpse the nature of God.

Christian mysticism is the tradition of mystical practices and mystical theology within Christianity which "concerns the preparation [of the person] for, the consciousness of, and the effect of [...] a direct and transformative presence of God" or Divine love. Until the sixth century the practice of what is now called mysticism was referred to by the term contemplatio, c.q. theoria, from contemplatio, "looking at", "gazing at", "being aware of" God or the Divine. Christianity took up the use of both the Greek (theoria) and Latin terminology to describe various forms of prayer and the process of coming to know God.