Why Not Be Changed Into Fire?

One day Abbot Lot came to his teacher, Abbot Joseph, and said, "Father, as best as I am able, I keep my little fast, my little rule, my little prayer. But it's not enough. And father, as best as I am able, I keep my meditation and my contemplative silence and I strive to cleanse my heart of all unnecessary desires. But it's not enough. I still haven't found what I seek. Father, what shall I do?

In reply, Abbot Joseph, the Elder, rose up and stretched out his hands to the heavens and his fingers became like ten burning lamps and he said "Why not be totally changed into fire?"