How did Odysseus reveal himself during the challenge?

Odysseus revealed himself during the challenge of the bow in his own hall in Ithaca. This event takes place in Homer's epic poem, "The Odyssey," specifically in Book 21 titled "The Test of the Bow."

Upon returning home after 20 years, Odysseus found his home overrun by suitors vying for his wife Penelope's hand in marriage, believing Odysseus to be dead. To delay and test the suitors, Penelope announced a challenge: whoever could string Odysseus's great bow and shoot an arrow through twelve axe handle sockets would win her hand.

When the day of the challenge arrived, none of the suitors were able to string the bow due to its immense strength and tension. Then, disguised as a beggar and unrecognized by the suitors, Odysseus took his turn. He confidently handled the bow, stringing it with ease, and then proceeded to shoot an arrow through the twelve axes, a feat only he was capable of performing.

This action revealed his true identity to his faithful servants and his son Telemachus. Following this dramatic display of skill and strength, he turned the bow on the suitors and, with the help of Telemachus and a few loyal servants, proceeded to deal with them for their disloyalty and disrespect.