How did the childhood experiences of Siddhartha Gautama lead to his questioning of the spiritual practices of his time
We don't know. Accounts of his life were written many years after he died by people who idolized him. However, this article sums up what many think influenced him.
http://encarta.msn.com/encyclopedia_761552413/Buddha.html
Here's another -- again, as Ms. Sue said, not very detailed about certain parts of his life:
http://www.wsu.edu/~dee/BUDDHISM/SIDD.HTM
Siddhartha Gautama, also known as the Buddha, was deeply influenced by his childhood experiences, which led him to question the spiritual practices prevalent in his time. In order to understand how these experiences shaped his path, we should explore his biography and the events that took place in his early life.
1. Birth and Luxury: Siddhartha was born into a royal family and led a highly privileged life. He was shielded from the harsh realities of the world, and his father ensured that he grew up amidst luxury and comfort. This upbringing provided him with material abundance but shielded him from the suffering and struggles that many people faced on a daily basis.
2. Encountering Suffering: Despite the efforts to isolate Siddhartha from the world's suffering, he eventually encountered it. As a young man, he ventured outside the palace walls and witnessed the harsh realities of life: aging, sickness, and death. These encounters deeply impacted him and made him question the purpose and meaning of life.
3. The Four Encounters: According to traditional accounts, Siddhartha had four encounters during his ventures outside the palace walls. He encountered an old man, a sick person, a decaying corpse, and finally, a peaceful monk. These encounters exposed him to the inevitable realities of human existence – the suffering, impermanence, and the desire for spiritual liberation.
4. Dissatisfaction with Spiritual Practices: Growing up, Siddhartha was raised in the Hindu religious tradition and was exposed to various spiritual practices of his time. However, these encounters with suffering challenged the effectiveness of these practices in addressing the fundamental questions of life. He began to question the notion that external rituals and ascetic practices could bring about true spiritual liberation.
5. The Great Departure: Driven by a deep longing for answers, Siddhartha decided to renounce his luxurious life and embarked on a spiritual quest. He left his home, family, and royal responsibilities behind in search of knowledge and understanding.
Overall, Siddhartha's privileged upbringing and subsequent encounters with suffering planted the seeds of doubt within him. These experiences made him question the adequacy of the spiritual practices prevalent in his society and motivated him to seek deeper truths. Eventually, these questions led him to develop his own philosophy and teachings, which became the foundation of Buddhism.