' The Pain of Love '...

The pain of love is the dynamite that breaks up the heart, even if it
be as hard as a rock.

Bowl of Saki, by Hazrat Inayat Khan

Commentary by Pir-o-Murshid Inayat Khan:

The effect of love is pain. The love that has no pain is no love. The
lover who has not gone through the agonies of love is not a lover, he
claims love falsely. ... Rumi describes six signs of the lover: deep
sigh, mild _expression, moist eyes, eating little, speaking little,
sleeping little, which all show the sign of pain in love. Hafiz
says, 'All bliss in my life has been the outcome of unceasing tears
and continual sighs through the heart of night.'

The sorrow of the lover is continual, in the presence and in the
absence of the beloved: in the presence for fear of the absence, and
in absence in longing for the presence. According to the mystical
view the pain of love is the dynamite that breaks up the heart, even
if it be as hard as a rock. When this hardness that covers the light
within is broken through, the streams of all bliss come forth as
springs from the mountains.