During a feast at Menelaus' table, the conversation turns to the hero Odysseus who is lost at sea. Many are participating in the discussion around the table, but Telemachus instantly cries at the mention of his father's condition. This serves to tip off Helen regarding his identity. Only a true loving family member could react so suddenly to such news.
The morning after positions Menelaus and Telemachus in almost a father-son moment. It is during this conversation that Menelaus learns the truth of Telemachus as Telemachus honestly reveals his purpose for travelling there.
In this moment, Menelaus relates to Telemachus by telling a story of his own trials which foreshadows the fact that Odysseus too will ultimately come home.
Helen uses her woman's intuition, Menelaus uses a fatherly inquiry.