Can you explain the analogy of the gem and the stone being polished, as mentioned in the teachings?

The analogy discussed in Chapter 19 serves to illustrate the Guru's expectations and the disciple's role. It states that both a stone and a gem are brightened when rubbed on a whetstone. However, the stone only becomes smooth while the gem becomes a brilliant jewel. The whetstone represents the Guru's guidance. This metaphor highlights that even with a powerful Guru, the disciple's inner quality is crucial. The Guru expects 'strong faith at the Guru’s feet and the strength of courage which is patience'—the inherent qualities of a 'gem'—to truly absorb the teachings and gain luster.