one thing i forgot to mention - as i moved to the hadith explanation.
rakhshan hilaal - means the crescent shines.
the crescent is harbinger of a new month, of celebration, of eid; and a metaphor for change - the dawn of a new era.
and it is that day in badr - with a constellation of stars surrounding the full moon - they heralded the dawn of a new era.
gird e mah dast e anjum mein rakshaN hilaal...
and the rise of the crescent - which banished the darkness of disbelief and injustice on the battlefield of badr.
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additional explanations:
hilal also means the crescent shaped whiteness on one's nails, and it is this alahazrat has alluded in another verse describing the beauty of his fingernails:
eid e mushkil kushayi kay chamkay hilaal
nakhunon ki bisharat pay lakhon salam
the crescent of the festival of the easing of hardship shine,
a billion salutes on the glad tidings given by his blessed fingernails..
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so the hilaal, in
gird e mah dast e anjum mein rakhshaN hilal
can also mean the blessed hands of the Prophet ﷺ
as he has said in another verse:
do qamar do panjah e khur, do sitaray das hilaal
unkay talway, panjay naakhun paa e at'har yeediyaan
two full moons, two suns, two stars and ten crescents
his (two) soles, his open palms, his feet and heels, and his fingernails
[open palms with five fingers spread are like a sun]
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one of the meanings of
hilaal is dust. and it is here that the Prophet ﷺ, threw a handful of dust which is described in the qur'an as: "you did not throw it when you threw; rather it was Allah who threw it" []
so the entire couplet can also be read as the description of RasulAllah ﷺ himself present in the battlefield of badr.
gird e mah, dast e anjum mein rakhshan hilaal
badr ki daf' e zulmat pay lakhon salam.
the allusion to dust (as one of the meanings) from his hand (dast) can also be drawn; the first word can also be read as gard=dust. these words are hints to other aspects of the event, though they are not direct translations.
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hilal also has another meaning: a spell of rain, and is an allusion to the rain that fell that night.
see taj al-arus, v31 p.146
Allah ta'ala knows best.