‘Abdul Muttalib thereafter constructed a few ponds close to the well of Zam Zam. He would fill these with Zam Zam water which he would provide to the pilgrims. However, during the hours of darkness, some jealous people would maliciously cause damage to these ponds. ‘Abdul Muttalib would then have to repair the damage early the next morning. Upset over these recurring, nasty acts, ‘Abdul Muttalib implored Allah Ta‘ala in du‘aa. He was divinely instructed in a dream to recite the following du‘aa:
اللّٰهُمَّ اني لا احلها لمغتسل ولكن هي لشارب حل
“O Allah! I do not render the water of Zam Zam Halaal for bathing. Rather, it is permitted only for drinking purposes.”
The very next morning, ‘Abdul Muttalib publicly announced this verdict. Thereafter, whoever attempted to damage any of the ponds would fall prey to some ailment or the other. When such woeful incidents of misfortune multiplied, the jealous people ceased damaging the ponds.
(Extracted from Seeratul Mustafa 1/36)