Valmiki Ramayana Bala Kanda Sarga 21 Shloka 9
Original Shlokaकृतास्त्रमकृतास्त्रं वा नैनं शक्ष्यन्ति राक्षसा:। गुप्तं कुशिकपुत्रेण ज्वलनेनामृतं यथा।।1.21.9।।
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कृतास्त्रम् trained in the use of arms, अकृतास्त्रं वा or untrained, कुशिकपुत्रेण by Viswamitra, गुप्तम् protected, एनम् this Rama, ज्वलनेन by flaming fire, अमृतं यथा like divine nectar, राक्षसा: rakshasas, न शक्ष्यन्ति will not be able to compete.
Trained or not in the use of arms, as long as Rama is protected by Viswamitra, just as nectar is protected by the flaming firegod rakshasas will not be able to compete with him.