When alchemists sought to change lead into gold, they were in fact looking for a way to change their dull, base lower nature into a higher nature

"Love is the law of life and nothing in Heaven or on earth can stop you from loving. But you must learn to love, in other words give your love a more spiritual dimension. Why? In order to work with this love. 'What do you mean, work? Love is pleasure, not work.' Yes, but who says you will no longer have any pleasure? You will have pleasure, but one that is far more subtle, far more complete, one that nothing will ever change, whereas pleasure as human beings generally understand it changes to ash sooner or later. There is pleasure that is like gold and there is pleasure that resembles lead. Gold does not rust, does not oxidize; it is always noble, precious and glittering. Lead on the other hand is shiny for a few moments when you first cut it, but very soon it tarnishes again. When alchemists sought to change lead into gold, they were in fact looking for a way to change their dull, base lower nature into a higher nature, divine nature. And this change is only possible when we replace pleasure with work."