The Lay of Leithian is an unfinished poem written by J. R. R. Tolkien during the 1930s. The poem is in rhyming couplets. The poem contains the story of Beren and Lúthien, a mortal man and an immortal elf maiden. It was published after Tolkien's death in The Lays of Beleriand, the 3rd volume of The History of Middle-earth.
The battle of Felagund and Sauron in songs of power is a poem from the Lay of Leithian, published in The Silmarillion:
He chanted a song of wizardry,
Of piercing, opening, of treachery,
Revealing, uncovering, betraying.
Then sudden Felagund there swaying
Sang in answer a song of staying,
Resisting, battling against power,
Of secrets kept, strength like a tower,
And trust unbroken, freedom, escape;
Of changing and of shifting shape,
Of snares eluded, broken traps,
The prison opening, the chain that snaps.
Backwards and forwards swayed their song.
Reeling and foundering, as ever more strong
The chanting swelled, Felagund fought,
And all the magic and might he brought
Of Elvenesse into his words.
Softly in the gloom they heard the birds
Singing afar in Nargothrond,
The sighing of the sea beyond,
Beyond the western world, on sand,
On sand of pearls in Elvenland.
Then the gloom gathered; darkness growing
In Valinor, the red blood flowing
Beside the Sea, where the Noldor slew
The Foamriders, and stealing drew
Their white ships with their white sails
From lamplit havens. The wind wails,
The wolf howls. The ravens flee.
The ice mutters in the mouths of the Sea.
The captives sad in Angband mourn.
Thunder rumbles, the fires burn--
And Finrod fell before the throne.
- Of Hunters Lore... OpenMic Video: Excerpt of the Lay of Leithian (Canto II) by Loren & Strumstick Messiah
J. R. R. Tolkien's Middle-earth legendarium