what does ethan infer when jot ham powell refuses a free meal

When Jotham returns with the horse, Ethan invites him in for dinner. Jotham refuses, which makes Ethan curious: Jotham never turns down a meal. Zeena must be in a foul mood because of something that happened on her trip. Jotham leaves, and Ethan goes back inside the kitchen to find it ready for supper.