It's in his nature

In an episode of Joan of Arcadia, God gives Joan the task of taking in and caring for a feral cat. Toward the end of the episode, the cat runs away and Joan sets out to track him down. All hope seems lost that she will find this cat when she runs into God in the park and explains that she tried but failed in her mission.

God says to Joan, "It's in his nature to run away." To which, Joan replies, "I thought I was supposed to change him." Then God again, "Why do you think it was him who was supposed to change?"