Based on Sai Baba's experiences, why is the virtue of patience so essential for a spiritual seeker?

Shri Sai Baba describes patience, or Saburi, as a cornerstone of a virtuous life. In the narrative from Chapter 19, he extols it as 'the manliness of men' and a powerful force that 'wards off sin, distress, and poverty.' He explains that patience is a 'mine of virtues' and the 'queen of the King of Good Thoughts,' capable of averting calamities and pushing away fear. Baba emphasizes that a person without patience, regardless of their scholarly knowledge or other virtues, leads a life that is ultimately 'in vain,' highlighting its indispensability on the spiritual path.