S. R. Faruqi:

Although the theme is light/trifling, it's new. It's possible that it might have been suggested by Bedil [in Persian]:

'Fear the sigh of the oppressed ones, for at the time when they send prayers
"Acceptance" comes to the door of God's court to welcome them.'

But in Bedil's verse there's a kind of awkwardness [infiʿāl], because he is threatening worldly oppressors. By contrast, in Mir's verse the sky is being awakened/alerted-- when a lament would emerge from the mouth of an oppressed one, the Lord knows what would be its status/situation then! The sky might break and fall, or the earth might be turned upside down.

To call the sky a ḥarīf of the affliction of the oppressed ones is fine. Here, ḥarīf means 'companion' and 'friend'. The root meaning of ḥarīf is 'fellow craftsman' and 'sharer in activity' (in the [dictionary] muntaḳhab ul-luġhāt ); these meanings are even more appropriate.

The suggestion is also fine, that if the sky doesn't become a ḥarīf in the sorrow and affliction and trouble of the oppressed ones, then the oppressed people will show endurance/fortitude, they won't sigh. But when the sky too would become a fellow-craftsman and friend of the affliction of these wretched ones, then the oppressed ones will not restrain themselves. And when in such a condition they sigh, then the Lord knows what would happen.

The structure and grammar of the second line is also fine. Its prose will be like this: kyā jāne nāle ke muñh se nikle kyā samāñ ho . But probably for the sake of dramaticness and immediacy [faurīpan], Mir omitted the muñh se nikle par and other such details. Now there's immediacy in the expression-- as if at one instant the lament emerged from the mouth, and at the next instant devastation arose.

Because of its insha'iyah style, dramatic tone, and 'tumult-arousingness', and because the sky has been confronted with the affliction of helpless ones, Mir's opening-verse is in a peerless class by itself. But the theme of the sigh and the sky, Zamin Ali Jalal has versified with quite new style and individuality:

maiñ ne uṭhā ke jaur tire muñh se uf nah kī
ḳhvud gar paṛe falak to mirā iḳhtiyār kyā

[I, having endured your cruelty, didn't do an 'oof!' from my mouth
if the sky itself would fall, then what control do I have?]

In Jalal's second verse, the 'affair-evocation' has advanced beyond even that of the verse above. The psychological truth of the situation, and the hint of triumph in the speaker's tone, are also fine:

lo imtihān tum mire nāloñ kā shauq se
kyūñ ḍar ke āsmān ke nīche se haṭ gaʾe

[make a test of my laments, at your pleasure!
why have you become fearful and moved away from beneath the sky?]

In Mir's verses there's peerless 'tumult-arousingness' and universality; in Jalal's verses there's a small scene, but nevertheless he has versified them well.

FWP:

SETS == GRANDIOSITY
MOTIFS
NAMES
TERMS

In the case of ḥarīf , the adjectival meanings too work well: the sky is warned not to be 'clever', or 'facetious', or 'impudent' (see the definition above) with regard to the affliction of the forlorn ones.

Note for grammar fans: Modern usage would be muñh se nāle ke nikalne par , 'on the emergence of the lament from the mouth'. The combination of archaism and reversed word order makes it a bit obscure. We can't take it as muñh se nikle ( huʾe ) nāle , because then we'd need kā instead of ke .