Why is telemachus fearful when his father first reveals his identidy?

Telemachus is initially fearful when Odysseus reveals his identity because he struggles to believe that his father, whom he thought was lost, has returned. The suddenness of the revelation and the possibility of facing the wrath of the suitors heighten his anxiety. Additionally, the overwhelming emotions of joy and disbelief make it difficult for him to process the situation, leading to a moment of fear and confusion.