अन्वयः

महात्मा great soul, सा that, कृतागसम् has done harm, दशग्रीवं to Ravana,न हन्ति not killed, इति यत् this being so, नियत: of good conduct, समुदाचारः chaste, भर्तरि towards husband, उत्तमा high, भक्तिः devotion

Summary

"Ravana is a great soul because, even though he has done harm to her, he is not killed. This is so because Sita being a chaste woman of good conduct and deep devotion towards her husband (she refrained from killing Ravana as she wanted her husband to do that.)

पदच्छेदः

नियतः	नियत (√नि-यम् + क्त, १.१)
समुदाचारो	समुदाचार (१.१)
भक्तिर्	भक्ति (१.१)
भर्तरि	भर्तृ (७.१)
चोत्तमा	च (अव्ययः)–उत्तम (१.१)

छन्दः

अनुष्टुप् [८]

छन्दोविश्लेषणम्

१	२	३	४
नि	य	तः	स
मु	दा	चा	रो
भ	क्ति	र्भ	र्त
रि	चो	त्त	मा