Such memories
stirred in the young prince a deep desire to grieve
for Odysseus. Tears streamed down his cheeks
and wet the ground when he heard his father’s name,
both hands clutching his purple robe before his eyes.
Menelaus recognized him at once but pondered
whether to let him state his father’s name
or probe him first and prompt him step by step.
– Homer
The Odyssey, Book 4, lines 126-133. When Menelaus grieves the loss of Odysseus, not knowing if he is dead of alive, Telemachus cries at this mention of his father. An observant Menelaus witnesses this and recognizes who Telemachus is straight away.