Listen, be watchful if you want a clear heart,
for something is born to you from every action.
And if you have an even greater hope than this,
and if the work goes beyond the rank of one who’s watching,
even though you’re dark as iron,
practice polishing, polishing, polishing,
so that your heart might become a mirror full of images,
with a lovely light-hearted one shining from every direction.
Though the iron was dark and lacking light,
polishing cleared the darkness from it.
[Mathnawi IV: 2467-2471]