Why did Indra flee after slaying Vritra and why did he cook dog meat?
Let us begin with the beginning. RV.1.32 (14)- "aher yatar kam pashya Indra hridi"(after seeing Ahi (Vritra)reduced Indra by heart)"yat te jaghnuso bhir gachchat" (there you killed those fleeing by fear)
"Nav cha yan navati cha sravanti"(those nine and ninety (water sources)are flowing) "shyeno na bhito ataro rajansi" (shyena (Indra ) has broken by moving around the dominion).
Thus we find here in the first line " yat te jaghnuso bhir gachchat" that Indra killed those fleeing away by fear and not that Indra became fearfull and fled himself.This mis-interpretation was carried into later scripture to justify that Indra flew away for the commiting sin of 'Brahma Hatya'.
Second RV.4.18 (11-13) The interpretation of hymn(11) is almost right except that term Mahish is an adjective for Indra's mother thereby meaning a dominant lady and not as 'trail of buffalo'.
The hymn (12) could also be interpreted differently as " who can make your mother widow in this circle of habitation, who can kill you while you wander around; who can be more merciful than you among gods,by moving forward you minimised (the importance of) your father (ancestor) while moving on their foot- print. Here the term 'prakshina' does not mean killing.
The hymn (13) is the narration by Gautama Rishi of his own condition. Almost all translators agree on this point. I can't think of any translator who can put Indra in bracket before the translation.However the translation is good enough except the last para where translator misses to point out who sent Madhu through shyena and it is 'madhva jabhar'(Indra knowing). Thereby meaning that after knowing the condition of Rishi Indra sent madhu(honey) through Shyena.
The hymn (13) could be the root of the later myth that Indra defiled Rishi Gautama's wife Ahilya.
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