S. R. Faruqi:

shaan = honor, condition, task
saarii = flowing, moving

In Urdu, ak;sar means 'usually, mostly'. For example, ak;sar logo;N ne samundar nahii;N dekhaa hai ; or gaa;Rii ak;sar der se aatii hai . But in its original meaning it's only 'abundance, greater part', because it's derived from ka;siir . Thus the meaning of the first part of the first line would be 'the grandeur and dignity of passion is endlessly abundant with regard to rank and number'. Since arfaa(( is derived from rafii(( , along with the grandeur of passion being endlessly abundant, it's also limitlessly and endlessly lofty. Here shaan can also mean 'condition' or 'task'.

Another interpretation is that the grandeur and dignity of passion usually, or mostly, is endlessly lofty. In the second part of the line shaan means only 'condition'. The word ((ajaa))ib is extremely fine. Because in the light of Urdu idiom it evokes enchantments and astounding/marvelous things. (In fact :tilismaat-o-((ajaa))ib is everyday speech in Urdu.) When ((ajaa))ib is used for for something in the singular, then it's taken as derived from ((ajiib . For example, ba;Rii ((ajaa))ib jagah hai .

Now, in order to give a 'proof' that the condition of passion is extremely astounding/marvelous, in the second line he's shown two conditions that are opposite and out of the ordinary. Sometimes passion flows and moves around in the mind and heart, and sometimes it becomes judaa (that is, 'different', or 'separate'). The truth is that both conditions are expressed absolutely correctly. He's composed an extremely fine verse.

FWP:

SETS
MOTIFS
NAMES
TERMS == PROOF

My translation reflects SRF's second interpretation, because it rests on the normal Urdu sense of ak;sar and just generally feels better grounded to me. What I find piquant about the first line are the two occurrences of shaan . Since they're divided by a 'but', we're led to think of them as somewhat contradictory or at least discrepant. And the range of meaning for shaan is so wide (see the definition above) that they easily can be read as such. In my experience, the meaning of 'grandeur, glory, pomp' is more common; but Platts presents it as secondary to the more neutral sense of 'thing, affair, condition'. As so often, Mir has left us to decide for ourselves what each of the shaan occurrences means, and how they fit together.

In the second line, the secondary meaning of judaa as 'peculiar, extraordinary' is also enjoyable. In that sense sab se judaa might become a superlative ('more extraordinary than all [others]'). Of course, in its primary sense of 'separate' it provides a wonderful effect of paradox: passion flows and circulates through everything; but it's also apart, separate, from everything, it's in a class by itself.