3 improved ramayana link to chapter
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"Sage Vishvamitra satisfied with the behaviour of Rama in obliging the orders of elders and performing the act that is assigned to him, gives many weapons to Rama, called śastra, astras. The weaponry is categorised mainly into two types. One is śastra - a handheld weapon like sword, lance or mace. The other is astra - a projectile missile invoked by reciting hymns."

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"Sage Vishvamitra satisfied with the behaviour of Rama in obliging the orders of elders and performing the act that is assigned to him, gives many weapons to Rama, called śastra, astras. The weaponry is categorised mainly into two types. One is śastra - a handheld weapon like sword, lance or mace. The other is astra - a projectile missile invoked by reciting hymns."

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"Sage Vishvamitra satisfied with the behaviour of Rama in obliging the orders of elders and performing the act that is assigned to him, gives many weapons to Rama, called śastra, astras. The weaponry is categorised mainly into two types. One is śastra - a handheld weapon like sword, lance or mace. The other is astra - a projectile missile invoked by reciting hymns."

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2 Improved sections
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1) Ramayana: In the introductory notes on the English translation of the Ramayana by Desiraju Hanumanta Rao & K. M. K. Murthy:

"Sage Vishvamitra satisfied with the behaviour of Rama in obliging the orders of elders and performing the act that is assigned to him, gives many weapons to Rama, called śastra, astras. The weaponry is categorised mainly into two types. One is śastra - a handheld weapon like sword, lance or mace. The other is astra - a projectile missile invoked by reciting hymns."

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2) According to A. C. Bhaktivedanta Swami Prabhupāda in his English translation of the Śrīmad Bhāgavatam, astra concerns "weapons shot as arrows" and śastra concerns "other weapons".
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3) Ramayana: Quoting M. Lakshmi in his article "Mareecha in Valmiki and Adhyatma Ramayana" (2003):

3) Bhagavata Purana: According to A. C. Bhaktivedanta Swami Prabhupāda in his English translation of the Śrīmad Bhāgavatam, astra concerns "weapons shot as arrows" and śastra concerns "other weapons".
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4) Lalita-Sahasranama: According to Ravi in his commentary on the Lalitā-sahasranāma, name 79:

1) In the introductory notes on the English translation of the Ramayana by Desiraju Hanumanta Rao & K. M. K. Murthy:

"Sage Vishvamitra satisfied with the behaviour of Rama in obliging the orders of elders and performing the act that is assigned to him, gives many weapons to Rama, called śastra, astras. The weaponry is categorised mainly into two types. One is śastra - a handheld weapon like sword, lance or mace. The other is astra - a projectile missile invoked by reciting hymns."

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2) According to A. C. Bhaktivedanta Swami Prabhupāda in his English translation of the Śrīmad Bhāgavatam, astra concerns "weapons shot as arrows" and śastra concerns "other weapons".
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3) Quoting M. Lakshmi in his article "Mareecha in Valmiki and Adhyatma Ramayana" (2003):

4) According to Ravi in his commentary on the Lalitā-sahasranāma, name 79:

1) Ramayana: In the introductory notes on the English translation of the Ramayana by Desiraju Hanumanta Rao & K. M. K. Murthy:

"Sage Vishvamitra satisfied with the behaviour of Rama in obliging the orders of elders and performing the act that is assigned to him, gives many weapons to Rama, called śastra, astras. The weaponry is categorised mainly into two types. One is śastra - a handheld weapon like sword, lance or mace. The other is astra - a projectile missile invoked by reciting hymns."

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2) Ramayana: Quoting M. Lakshmi in his article "Mareecha in Valmiki and Adhyatma Ramayana" (2003):

3) Bhagavata Purana: According to A. C. Bhaktivedanta Swami Prabhupāda in his English translation of the Śrīmad Bhāgavatam, astra concerns "weapons shot as arrows" and śastra concerns "other weapons".
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4) Lalita-Sahasranama: According to Ravi in his commentary on the Lalitā-sahasranāma, name 79:

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First of all, the etymological definition of both, according to Monier-Williams:

śastra, √śas (to cut, kill, slaughter) (1) (2)
– an instrument for cutting or wounding, knife, sword, dagger
– a weapon which is handled

astra, √as (to throw, cast, shoot at) (1) (2)
– a missile weapon, bolt, arrow
– a weapon which is thrown

Technical definitions:

1) In the introductory notes on the English translation of the Ramayana by Desiraju Hanumanta Rao & K. M. K. Murthy:

"Sage Vishvamitra satisfied with the behaviour of Rama in obliging the orders of elders and performing the act that is assigned to him, gives many weapons to Rama, called śastra, astras. The weaponry is categorised mainly into two types. One is śastra - a handheld weapon like sword, lance or mace. The other is astra - a projectile missile invoked by reciting hymns."

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Note that this chapter mentions the various astras used and the following chapter mentions the counter-astras.

In the footnotes:

"There are some verses that depict the nature of these astras. A few of them are given under. Though we may not actually acquire a projectile power with these verses, they may at least detail what these missiles are. The source of these verses is untraceable, but they are said to be in puranas..."

2) According to A. C. Bhaktivedanta Swami Prabhupāda in his English translation of the Śrīmad Bhāgavatam, astra concerns "weapons shot as arrows" and śastra concerns "other weapons".
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3) Quoting M. Lakshmi in his article "Mareecha in Valmiki and Adhyatma Ramayana" (2003):

"While slaying Tataki, Rama used a Sastra. Arrows may be divided as Sastras and Astras. A Sastra can only be used once. An Astra can be used again and again. If one uses the Astra, it does its work and comes back to the user. By chanting the prescribed Mantra one has to purify the Astra."

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4) According to Ravi in his commentary on the Lalitā-sahasranāma, name 79:

"She counters the weapons used by Bhandāsura, by using Her own. Here, two types of weaponaries are mentioned. One is astra that is thrown at the enemies in a battle field. Modern day bombs can be compared to this. Another is śastra, which is always held in hand, like a gun. The weaponaries of Lalitai aids our efforts in attaining bliss by destroying avidyā. Weapons coming out of Her hands are aimed at us in destroying the illusion of duality."

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Marathi:

Finally the grammatical definition of the words in the Marathi language:

śastra (शस्त्र).—n (S) A weapon. 2 A weapon figuratively, that in which one's prevalence or power consists;--as learning, beauty, sanctity, the pen &c. Applied also to any thing considered as the masterer, match, vanquisher, antidote &c., of any other thing. śa0 tuḷaṇēṃ or tōlaṇēṃ To point or set or hold in position one's weapon: also to wave or brandish it. śa0 dharaṇēṃ with vara of o. To take up arms against.

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astra (अस्त्र).—n (S) A weapon charmed by the recitation over it of some mystic formula: also the formula or mantra. Ex. of comp. agnyastra, vārūṇāstra, mēghāstra, sarpāstra, astravidyā, astraprayōga. 2 S A Weapon gen.

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