Shao was not born a priest, or a Monk, or anything of the sort. He was a street rat. Not an orphan or abandoned, but left mostly to his own devices as a child. He roamed the streets of his own city with a gang of like-minded children, laughing and playing, and even occasionally stealing...but usually no more than a treat of a piece of fruit or candy. His life was simple, and his family was poor, but he was happy.
However, as he grew older he grew more dissatisfied with his life, felt that he should be doing something more important than eking out an existence in the slums of his home town, many of his friends moved on to find work and having little time for their previous shenanigans. At the ripe old age of 12 he set his sights high, vowing to become the best human being he could possibly become.
To do so, he figured he should go to the source, to the one being who had achieved such perfection. He went to the nearby temple of Irori, and asked to speak with the god.
The monk at the door chuckled softly, and told the boy that he couldn't just commune with a god so easily. He'd need to hone his mind and spirit, through training, to achieve such a goal.
And so the boy entered into the temple, and did not step foot outside it again until he was deemed worthy by the priests and monks of the order, with a greater understanding of the undertaking he had so naively set for himself as a child.
He wandered for a while, attempting to maintain serenity, keeping his skills sharp, his spirit pure, and his mind unclouded.
However, he felt that the pieces had not quite yet clicked for him. He had the training of a Monk, ready to independently study his art and find his soul, but his worldly experience with anything besides the slums and the inside of the monastery was nonexistent.
And so, he joined the military, hoping to expand on his monastic training with real combat experience, and to see more of the world. He saw may battles and honed his skills, and finally found what he had originally sought, a connection to Irori himself, becoming a conduit of his power on the Material Plane. Not fully a priest, nor a Monk, but something in between that, a holy soldier for his god.