In the Masnavi, Rumi introduces the concept of divine discrimination (tamyiz) bestowed upon inanimate matter. Using the historical-allegorical example of the River Nile, Rumi explains that the river distinguished between the Copts and the Israelites under God's command, turning to blood for the oppressors while remaining pure water for the believers.

Key aspects of this concept include:

1. Consciousness of Matter: Inanimate elements are not inert; they possess a divinely granted intelligence to obey and discern.
2. Divine Grace vs. Wrath: Physical behavior is governed by divine favor (lutf) and wrath (qahr). God's grace makes a physical river act intelligently, while His wrath can render human intellect (such as Cain's) foolish.