Srimad Valmiki Ramayana

Sita concludes her ultimatum by adding poison and fire to her list of exits. She ends with a definitive vow of fidelity: she will never touch a man other than Raghava. This is the final assertion of her chastity to refute the suspicion she projected onto Lakshmana. Tragic irony permeates this verse. She claims she will enter fire rather than touch another man; later in the epic, she will indeed enter fire (Agni Pariksha), not to avoid another man, but to prove she remained faithful despite being abducted by one. Her declaration here seals Lakshmana's departure, leaving the hermitage unguarded for Ravana.