This was written as an accompanying fic to Loyalty.
Defying his father and saving Merlin had brought Arthur to an important realization about the king.
When he had decided that he would have to return to Camelot he hadn't felt afraid or feared for his life. Somewhere in him he knew that his father would never really hurt him. Throw him in the dungeons yes, maybe have him lashed but never truly hurt him. He found that he believed that Uther could never hate him or wish real harm on his son. Somehow, somewhere Arthur knew that his father loved him and against all odds he felt safe, secure even in that knowledge.
Arthur didn't hate the king for what he had done to Merlin, not really. Since he was a small boy Arthur had idolized his father, doing anything he could to please him. Sadly, the fact that Uther almost never showed any pride towards his son, had simply pushed the prince harder in his attempts. So Arthur had become the best knight in Camelot but even that didn't seem to be enough.
It wasn't till the last few years, since Merlin had come, that Arthur had finally realized that Uther was only human, and not the idol he had seemed through his young son's eyes. Arthur had seen that his father had problems, pain and that he was indeed fallible.
This in a way took some of the anger that Arthur felt toward his father for things he had done. He still hated the things Uther did but he did not hate him. Although far from perfect, Arthur loved his father.