Laxman was in a fix. He knew that Ram could never get hurt, and secondly he was specifically asked by his elder brother to remain by the side of Sita. If he leaves Sita, he disobeys Ram which might bring some misfortune, and if he does not proceed to help Ram, Sita is displeased!
Still, as per the voice of his conscience, he requested Sita to remain calm as no difficulty can come Ram's way. She might have imagined the voice as of her husband. However, Sita was persistent in her demand that Laxman must go to Ram's rescue. At last, with a heavy heart, Laxman decided to go in search of Ram.
Before leaving Sita alone, he drew a line -the Laxman Rekha - that Sita should never cross. (In the event of any one including Sita crossing that Laxman Rekha, the person was sure to get burnt.) Sita promised not to cross the same.After that, Laxman went in search of Ram and the deer.
Ravan lifts Sita
Here near the hut, Ravan made his appearance as he was sure Ram and Laxman could not come back soon. He also, through his Mayawi Power changed himself into a monk - Sanyasin and as the custom went, came to the hut of Sita begging for food.
"Bhiksham dehi mai", said Ravan to Sita. (Give me food, O mother.) [In India, today also, it is customary to give alms and food to the begging sanyasin.]
With a tray of some fruits and food Sita came out of the hut at the call of the 'guest' at her door. However, she did not dare to cross the line drawn by Laxman lest she should get burnt, and hence, she offered the bhiksha from well within the limits of Laxman Rekha.
Sanyasin Ravan was also equally aware of the power of that line, crossing of which was sure to see his end! Therefore, pretending to be unhappy at Sita's reservation in serving a 'holy person' from a distance, he shouted, "O noble lady, have you forgotten the lofty and honoured tradition of your clan? How can I accept the alms given with reservation and insult! Please come out and give the offerings with propriety and decorum befitting your Aryan tradition."
Thus influenced, no sooner did Sita cross the line than the mighty Ravan took his chance and lifted Sita on his shoulders and fled away. The terrified lady shouted for help, but of no avail. Soon Ravan was flying high in the sky to take an aerial route towards his capital city -Lanka. Sita's cries for help could not reach distant Ram and Laxman.