"I hope it's just for show." Honestly, if he'd expected Akechi to be able to fight at all, he wouldn't have just drawn his knife and done nothing with it. That's an invitation to get attacked. He's currently reevaluating both this Akechi (a good and wise idea) and how often he should just go straight to stabbing (possibly less good).

He lowers the knife, but he doesn't fold it up again and he certainly doesn't put it back in his pocket. He eyes Akechi with new suspicion, and some level of confusion as well. It's almost like he became a different person for a split second, but then reverted.