Depict the scene of 'The Plague of Darkness' as described in Exodus 10:21-29, through the lens of respectful and devotional art associated with Christianity. The medium should be suggestive of watercolor techniques, showcasing soft transitions and a dreamy quality inherent to the medium. No text or words should be present in the image. The scene should visually encapsulate the intensity of darkness that befalls, while also tapping into the spiritual and religious significance of the event as portrayed in Christian theology.