Meaning
To do something contrary to all custom and sense.
Literally: to make the Ganga flow backwards
See it in the verse
Ulti ganga bahana in Iqbal’s couplets
Jhapatna palatna palat kar jhapatna
Lahu garm rakhne ka hai ek bahana
Lahu garm rakhne ka hai ek bahana
To swoop, to wheel away, and to swoop once more — it is only a pretext for keeping the blood warm.
The Falcon · Action · Restlessness
Ai aab-e-rud-e-Ganga wo din hai yaad tujh ko
Utra tere kinare jab karwan hamara
Utra tere kinare jab karwan hamara
O waters of the river Ganga, do you remember those days — when our caravan first halted upon your banks?
Unity · Love