S. R. Faruqi:

He has expressed this theme a number of times, sometimes with regard to the beloved, sometimes with regard to the lover. From the first divan [{361,8}]:

hai amr-e sahl chaahat lekin nibaah mushkil
patthar kare jigar ko tab to kare vafaa))e;N

[desire is a simple act, but maintaining it is difficult
let one make his liver into stone, then show faithfulnesses]

From the second divan [{972,2}]:

sa;xtii bahut hai paas-o-muraa((aat-e ((ishq me;N
patthar ke dil jigar ho;N to ko))ii vafaa kare

[there is much harshness, in the respect and regard for passion
if one would have a heart and liver of stone, then let him show faithfulness]

From the fifth divan [{1739,5}]:

patthar kii chhaatii chaahiye hai miir ((ishq me;N
jii jaantaa hai us kaa jo ko))ii vafaa kare

[it's necessary to have a breast of stone, Mir, in passion
his inner-self knows, who would show faithfulness]

From the sixth divan [{1853,2}]:

((ishq karnaa nahii;N aasaan bahut mushkil hai
chhaatii patthar kii hai un kii jo vafaa karte hai;N

[to do passion is not easy, it's very difficult
he has a breast of stone, who shows faithfulness]

The present verse is better than all of them, for several reasons. First of all, look at the wordplay of 'Pari' and 'glass' (they capture Paris within glass).

Then, he's called the Pari 'delicate like glass' and those who show faithfulness 'stone-hearted' (the heart too is called 'delicate like glass').

Then, he hasn't allowed the Pari to come even as far as the idea/utterance of showing faithfulness and has said 'don't make a claim of/for love'. That is, he hasn't allowed her to come even to the stage when faithfulness and unfaithfulness would have been encountered.

In the process, he has rescued the beloved from the charge of unfaithfulness and unkindness; and has given this proof: that 'you are delicate'. That is, if she doesn't show kindness and faithfulness, then this is the grandeur of a beloved, and the grandeur of beauty as well. It's a fine verse.

An opening-verse by Shan ul-Haq Haqqi has a theme similar to this one, and it's very enjoyable:

tum se ulfat ke taqaa.ze nah nibaahe jaate
varnah ham ko bhii tamannaa thii kih chaahe jaate

[by you, the claims of love are not upheld
otherwise, even/also we had a longing to be desired]

FWP:

SETS == IZAFAT
MOTIFS
NAMES == PARI
TERMS == THEME

It's easy to see why SRF prefers the present verse to the others that he adduces: the others concern themselves chiefly with the need to acquire a 'heart of stone' in order to be strong enough to be faithful through passion's painful vicissitudes. That's understandable within the contexts the verses provide, but not too surprising in itself.

The present verse, more complexly, assumes the 'heart of stone' already, and adds the contrasts of glass with stone and of the Pari with the lover. The assumption is piquant in itself, because at first it seems counter-intuitive (we don't normally think of the lover as having a heart of stone); but Mir trusts us in the audience to be quick on the uptake, so that we can supply the reasoning ourselves, on the fly, in time to appreciate the particular contrasts adduced by the verse.

What kind of claim is the Pari instructed not to make? The izafat gives us choices. Perhaps it's a claim 'of' kindness or favor or affection (a claim that she is not cruel but in fact treats her lovers well), or it could be a claim 'for' kindness or favor or affection (a demand that her lovers show her more intimacy and love). Or perhaps she's even falling in love with someone herself, and might be seeking to establish her deservingness as a lover.

In any case, according to this verse she's just not cut out for it. Either she'd need to show a heart of stone herself (which is impossible for such a delicately glassy being) or she'd need to stand up to an encounter with hearts of stone in her lovers (which would certainly shatter her glass-like self). Since Paris are made of fire, it seems that their delicacy should be tempered with a certain hot fierceness, but the present verse chooses to take a different tack.

Note for grammar fans: Is the Pari delicate like glass (where se is short for jaise ), or is she 'more delicate than' glass (where the full form would be shiishe se ziyaadah naazuk )? In this verse it's hard to tell, but it also hardly matters.