"It depends on which stories you have heard," Arthur noted. He was a little curious as to what they were, but was not sure he should really ask.
Robin's explanation of his own renown-- infamy, rather, from the sounds of it-- gave him pause. Uprisings against leadership due to harsh punishments were quite familiar to Arthur; in fact, a majority of his work with the army was making sure nothing like that succeeded. Yet, Robin had also said that his people were being widely oppressed, which changed the situation considerably. Hoping he was making the correct judgment, Arthur decided to trust that Robin had done the right thing.
Gesturing for Robin to lead the way, Arthur said, "Consider me a constant opportunity." Neither of them were armored, so it might make more sense to retrieve practice swords; but if Robin was as skilled as he implied, using their own weapons would be preferable.