A "Tare" is a weed.
The parable Jesus gave was about weeds in the wheat. If we apply that to today we would consider the religeouse lost man sitting in the pew in front of you.
You assume he is saved because he is sitting in church in front of you. We always will have people who infiltrate our ranks, the Ananiases and Sapphiras and the Judas Iscariots would be examples.
When asked about pulling the "tares" from the wheat, Jesus said NO. I will take care of them at the harvest.
But it is not our job to pull weeds today. Our job is to plant seeds of the gospel. We don't see a person's heart. Our concern should not be who the hypocrites are but whether we are hypocrites ourselves. Our job is to take care of ourselves, to take heed and make sure that we are true believers.