mai;N ne rokaa raat ;Gaalib ko vagarnah dekhte
us ke sail-e giryah me;N garduu;N kaf-e sailaab
thaa
1) I stopped Ghalib last night, otherwise [you/we] would have seen
2a) in his torrent of weeping, the sky would have been foam of the
flood
2b) in his torrent of weeping, the sky was foam of the
flood
SETS == DIALOGUE;
VARNAH
SKY {15,7}
On the twofold grammar of varnah (of which vagarnah is an archaic full form) see {15,12}.
The lover either did weep the sky into a mass of foam (clouds), or would have done so if he had not been stopped by a prudent bystander. This 'cosmos-destruction' theme involves sometimes weeping, and sometimes fire. Usually these cataclysms seem to occur only in the lover's own world, but in other verses, like this one, they appear to be evident and dangerous to ordinary human beings as well.
Compare this verse with its less fortunate, unpublished cousin, {15,16x}.
Nazm:
That is, the flood of tears would have reached up to the sky. (17)
Bekhud Dihlavi:
He says, last night I prevented Ghalib from weeping-- otherwise, you would have seen the spectacle that his flood of tears would have reached to the sky and become a torrent of water. (34)
Bekhud Mohani:
That is, the sky would have swum in water the way foam does in a flood. The Ustad of the Age so decrees it. It's worth seeing, where he has put thaa. (38)