...Verily! Those on whom you call besides Allah, cannot create (even) a fly, even though they combine together for the purpose...

"O mankind! A similitude has been coined, so listen to it (carefully): Verily! Those on whom you call besides Allah, cannot create (even) a fly, even though they combine together for the purpose. And if the fly snatched away a thing from them, they would have no power to release it from the fly. So weak are (both) the seeker and the sought. 
They have not estimated Allah His Rightful Estimate; Verily, Allah is All-Strong, All-Mighty."

Reference: 22-73-74 

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