Board Thread:General Discussion/@comment-26491272-20150613000358/@comment-5674726-20150615225255

Yes. In the first episode of the second season, they show how risky it is to take on staff without performing a background check when Cedric was able to weasel his way into Arthur's employ. If he had intended to kill Arthur rather than steal from him, he could have poisoned him or stabbed him in his sleep. They also had a spy in the royal household an episode later. Merlin didn't intend to harm Arthur but if an assassin wanted to get close to him, ingratiating himself in the hope of being appointed to the royal household wouldn't be a bad strategy.