The Odyssey help me with homework: In book 17, Athena urges Odysseus to beg from all of the suitors

In book 17, Athena urges Odysseus to beg from all of the suitors to “test them, so we can tell the innocent from the guilty,” even though she doesn’t plan to spare any of them. Why would she do this? What does it show about Odysseus’ character that he not only complies, but really throws himself into the role, especially with Antinous?