Disclaimer: Tolkien, it is all his.
It never left him – the hunger. However much he consumed, he was never sated. Whereas he might once have controlled his voracious appetite, he chose to give it full reign. Now, it all but devoured him.
Power, absolute power, tastes so sweet on the tongue. Its corruption is as insidious as decay attacking a healthy tooth. The rot finds a tiny weakness and destroys from within. Saruman had long ago developed a sweet-toothed yearning for power and now it was a constant ache impossible to satisfy...
The Ring – his mouth watered at the thought ...and his want consumed him utterly.