Odysseus puts beeswax in his men’s ears to block the Sirens’ song. The plan comes from Circe, who explains that anyone who hears the Sirens will be enchanted and never return home.
Odysseus does not place the wax in his own ears because he wants to hear the song. Instead, his sailors soften and press the beeswax into one another’s ears, then bind him upright to the mast. This lets him listen without being able to steer the ship toward the Sirens.
The detail is sometimes shortened in retellings to simply “wax,” but Homer’s account specifies sweet, kneaded beeswax. Pitch and resin are different substances and are not the material named in the Odyssey. Once the ship has passed beyond hearing distance, the crew removes the wax and unties their captain.