The reality is that every local church is impure because not everyone in it is pure. Do we weed out the impure ones? If so, we will end up with an empty building.
The sentiment here is a good one - purity and holiness. But it is not practical or even desirable to have a church which is above reproach.
Such a church would by definition be pharaisaical in their minds, hearts and lives.
Its focus would be on behavior rather than faith.