Question
Soil for Maa Durga puja
Answer
As we know, prostitution is considered as taboo in Hindu Religion.
So when a person decides to have sex with a prostitute, he is aware that he is going to do a bad thing, and hence he loses his good deeds/goodness outside the brothel.
As many people visit the brothels, the soil outside holds all the goodness which are lost by those people, think as if the goodness is shed in that soil by the people who visit there and hence that soil is used to create idols as it is considered as pure/filled with good deeds.
To support my answer, I found this, to refer...
The Pujari goes personally to Nishiddho Pallis, Sonagachi to beg for dust from a prostitute. It is believed that a man who enters a brothel leaves all his purity and virtues there. Therefore, making the soil of a brothel pure.
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