Why did Siddhartha struggle with this Self when he was a Brahmin and an ascetic?

Siddhartha struggled with this Self for a few reasons. First of all, he felt that too much knowledge had hindered him. He had gone through too much mortification of the flesh and too many sacrificial rites. There was too much doing and striving in his life. "Hed had been full of arrogance; he had always been the cleverest, the most eager - always a step ahead of the others, always the learned and intellectual one, always the priest or the sage. His Self had crawled into this priesthood, into this arrogance, into this intellectuality. It sat there tightly and grew, while he thought he was destroying it by fasting and penitence" (Hesse 99). Siddhartha realized that inward voice had been correct, and that only he could bring himself to salvation. For this reason Siddhartha went out into the world and became an avaricious merchant, a dice player, a drinker and a man of property. He had to do all of these things until the priest and Samana inside of him were dead. Now he reproached the way he lived in his former life and had found equanimity in his new ways. Siddhartha felt as though he had died and awakened as a new person from his sleep. For the first time in a long time, Siddhartha was very happy with his life. He was content with the world around him and found joy in everything he saw. "Smiling, he listened to his stomach, listened thankfully to a humming bee. Happily he looked into the flowing river. Never had a river attracted him as much as this one. Never had he found the voice and appearance of flowing water so beautiful" (Hesse 100). Siddhartha won the battle with his Self and now understood what he was supposed to do.