Question
How many days did Ravana keep Sita confined?
Answer
Ravana kidnapped maa Sita in the season of Hemanta (comes before winter) and had given Her twelve months time to make up Her decision to accept Ravana before his demons kill Her:
शृणु मैथिलि मत् वाक्यम् मासान् द्वादश भामिनि ||
कालेन अनेन न अभ्येषि यदि माम् चारु हासिनि |
ततः त्वाम् प्रातः आशा अर्थम् सूदाः छेत्स्यन्ति लेशशः || [VR - 3.56.24,25]Meaning
Oh, angry lady Maithili, listen to my words. A period of twelve months is given to you. And oh, smiley smiler, if you do not come nigh of me within that period, then the cooks will slice you to pieces for the purpose of a morning meal
When Hanuman met maa Sita in Panchavati (2nd September 7292 B.C.), She told him that only two months of Her life is left [VR - 5.58.106]. And just around 2 months later from the day of Hanuman's meeting with maa Sita (3rd November 7292 B.C), the final war, to rescue maa Sita, had started.
So Ravana kept maa Sita confined for around 12 months or roughly 365 days.
Source:
http://www.hindunet.org/hindu_history/ancient/ramayan/rama_vartak.html
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