FWP:
SETS == PARALLELISM
COMMERCE: {3,3}
EYES {3,1}
Nazm, Bekhud Mohani, Shadan (p. 475), Chishti (p. 691), and Mihr (p. 455) treat this and the next verse as a verse-set; Bekhud Dihlavi explicitly labels them as such. Baqir (p. 408) seems to treat them as a pair of some lesser kind. Josh (p. 284) treats them separately. As always, I follow Arshi, who treats them as ordinary, separate verses. It's possible to see why they might be read together, but it's also perfectly possible to read them separately without any sense of loss. (For further discussion, see {164,5}.)
On the whole, Ghalib doesn't make too much use of imagery drawn from the realm of commerce, but here he gives us a fine illustration of how it can be done. The eye is a broker or middleman who wheels and deals, and who may play both ends against the middle. Selling (though not producing) the 'merchandise of disgrace', the eye is a sort of drug dealer, soliciting customers in a furtive way, gesturing from a dark alley, knowing there will be takers for such seductive, addictive wares.
And what is the eye's relationship to the heart, that poor sucker, that masochist, that hapless customer? The heart is a 'buyer'-- but not of any material goods. What the heart is really seeking is the 'relish' or 'taste', either 'of', or 'for'-- and look at the wide range these these ambiguities open up-- some kind of 'lowness', 'vileness', 'abjectness', 'wretchedness' (see the definition above). At the instigation of the eye, the heart deliberately strays from the broad highway of proper behavior, into the alleys and byways where it can 'purchase' its own disgrace and humiliation.
How to assign responsibility for this sordid and undesirable state of affairs? Is it the wandering eye, the seeker-out and broker of all manner of forbidden fruits, that's to blame? Or is it the heart, the customer who ought to know better, who deliberately sacrifices his good repute for the sake of abject and illicit pleasures? The two lines of this verse seem to identify them as natural accomplices in their low-life transactions.
And who is turning in this police-blotter kind of report,
identifying their mutual culpability, if not the lover himself? But what is
his tone? Analytical, deprecatory, despairing, self-exculpatory, amused, wry?
The tone is everything-- and as so often, we have to invent it for ourselves.
Nazm:
[Commenting on this verse and {164,5} together:] That is the eye, acting as a broker, makes the heart absorbed in the merchandising [saudaa]. He has given the details of this in the second verse: that in a hundred ways the eye performs tear-shedding, which is a cause of disgrace, and in a hundred ways the heart laments, the result of which is abjectness/wretchedness. (177)
== Nazm page 177