In the season four episode 'Restless' Willow's dream includes her writing on Tara's back.  In the DVD commentary for 'Restless' Joss Whedon says that the writing is actually a Sappho Poem in the original Greek. 
I was curious so I got my Sappho Companion and worked out which poem it was.  I didn't have to look very hard because it is Fragment One, usually called 'An ode to Aphrodite.'  There are six different translations in the book so I am only including the earliest and most recent. 
They are both taken from 'The Sappho Companion' by Margaret Reynolds.
An Hymn to Venus

O  Venus, Beauty of the skies,
To whom a thousand Temples rise,
Gayly false in gentle smiles,
Full of Love-perplexing Wiles;
O Goddess! from my heart remove
The wasting Cares and Pains of Love

If ever thou hast kindly heard
A Song in soft Distress preferr'd,
Propitious to my tuneful Vow,
O gentle Goddess! hear me now.
Descend, thou bright, immortal Guest,
In all thy radiant Charms confest.

Thou once didst leave Almighty Jove,
And all the Golden Roofs above:
The Carr thy wanton Sparrows drew;
Hov'ring in Air they lightly flew,
As to my Bow'r they wing'd their Way:
I saw their quiv'ring Pinions play.

The Birds dismist (while you remain)
Bore back their empty carr again:
Then You, with Looks divinely mild,
In ev'ry heav'nly Feature smil'd,
And ask'd, what new Complaints I made,
And why I call'd you to my Aid?

What Phrenzy in my Bosom rag'd,
And by what Cure to be asswaged?
What gentle Youth I would allure,
Whom in my artful Toiles secure?
Who does my tender Heart subdue,
Tell me, my Sappho, tell me Who?

Tho' now he shuns thy longing Arms,
He soon shall court thy slighted Charms:
Tho' now they Off'rings he despise,
He soon to Thee shall sacrifice;
Tho' now he freeze, he soon shall burn,
And be thy Victim in his turn.

Celestial Visitant, once more
Thy needful Presence I implore!
In Pity come and ease my Grief,
Bring my distemper'd Soul Relief;
Favour thy Suppliant's hidden Fires,
And give me All my Hearts desires.

Ambrose Philips, 1711

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