What is an impure person forbidden to do? Can such a person become pure again?
An impure person is forbidden to enter the Temple or eat sacred foods, but currently those things don't exist. For more than 2000 years there have been two opinions about whether an impure person is allowed to pray; some people immerse themselves daily for this reason, but most people follow the lenient opinion. We don't have the ashes of the "red cow", so can't purify ourselves from contact with the dead, but we can purify ourselves from most other types of ritual impurity by immersion.
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