FWP:
SETS == CATCH-22; HERE/THERE; SYMMETRY
CATCH-22 verses: {9,7}; {14,3}; {15,2}; {24,5}; {41,3}; {78,3}; {84,1}; {95,6}; {97,1}; {97,3}; {112,2}; {121,4}; {145,3}; {151,7}; {153,1}; {161,6}; {174,5}; {177,1}; {184,2}; {189,5}; {198,2}; {202,5}; {203,4}; {205,1}; {209,8}; {215,5}; {231,9}; {233,11} // {314x,1}
HERE/THERE verses: {15,2}; {15,3};
{15,4}; {15,5};
{15,6}; {15,7};
{15,19x}; {24,6}; {25,8}, temporal;
{29,1}, implicit; {43,3}; {115,7};
{122,1}; {138,9x}*, abstract; {149,6x};
{153,4}, ardor vs. heart; {167,9}; {185,2};
{205,4} // {351x,5}; {402x,1}; {405x,2}
Despite Shadan's assertion, most editors and commentators don't treat {15,2-7} as a verse-set, but it's easy to see what Shadan means. Unlike the verses before and after them, these six are all structured around the contrast between vaa;N ('there', meaning in the beloved's world) in one line, and yaa;N ('here', meaning in the lover's world) in the other. The witty and appropriate parallels between these two worlds both disguise and reveal how radically incommensurable they are. Another such verse, that didn't make it into the divan: {15,19x}.
Sa'id's explanation has an elegant circularity: the beloved was prevented from coming by a rainstorm-- that is, by an effect of the flood of tears the lover wept when he learned she was not coming. Or perhaps it shouldn't be called circularity, but 'mutual causality'-- her behavior causes his behavior, and his behavior causes her behavior. Thus lover and beloved are intimately linked, even though they are (literally) poles apart. (After all, aren't the two poles intimately linked?) Another potential case of such mutual causality can be seen in {15,3}.
Sa'id's notion also amounts to a form of 'catch-22'. (The original 'catch-22', for those who don't remember the novel: you can only be excused from having to fly bombing missions if you're insane; but if you seek to be excused from flying bombing missions, this proves that you're sane.) The lover hopes to earn a visit because he weeps so much; but because he weeps so much, the beloved has a 'flood' excuse not to visit him.
The cotton of the lover's pillow was white like sea-foam, and from his weeping it was also just as wet (2a). Or, as Asi says, the sea-foam was all the pillow the lover had, since his own pillow had long since floated away (2b). The difference between (2a) and (2b) depends on the direction in which we choose to read the metaphor; the Urdu grammatical rule that I call 'symmetry' means that both are equally legitimate. There's a similar situation in {11,1}, which also involves waves of water and a hard-pressed lover (though in that verse the lover is much more confident).
Note for translation fans: It seems as though some use should be made of 'rein-ing in'!
Nazm:
That is, the rain prevented her from showing mercy, and I was in such a state from weeping and weeping that here, instead of a cotton pillow there was the foam of the flood. (15)
== Nazm page 15