Opposites

God created suffering and heartache so that
joyful-heartedness might appear through its opposite.
Hence hidden things become manifest through
opposites. But since God has no opposite, He remains hidden.
For the sight falls first upon light, then upon
color: Opposites are made manifest through opposites, like
white and black.
So you have come to know light through light's
opposite: Opposites display opposites within the breast.
God's light has no opposite within existence,
that through its opposite it might be made manifest.
Therefore our "eyes comprehend Him not, but He
comprehends the eyes" (Koran VI 104): Learn this from Moses at
Mount Sinai.
Know that form springs from meaning as the
lion from the thicket, or as voice and speech from thought.
Form was born from speech and then died. It
took its wave back to the sea.
Form comes out from Formlessness: Then it
returns, for "unto Him we are returning" (Koran II 156)

... Mathnawi, Mevlana Jalalludin Rumi