Here's one of his wonderful pieces:
You I choose, of all the world, alone;
Will you suffer me to sit in grief?
My heart is as a pen in your hand,
You are the cause if I am glad or melancholy.
Save what you will, what will have I?
Save what you show, what do I see?
You make grow out of me now a thorn and now a rose;
Now I smell roses and now pull thorns.
If you keep me that, that I am;
If you would have me this, I am this.
In the vessel where you give color to the soul
Who am I, what is my love and hate?
You were first, and last you shall be;
Make my last better than my first.
When you are hidden, I am of the infidels;
When you are manifest, I am of the faithful.
I have nothing, except you have bestowed it;
What do you seek from my bosom and sleeve?