The Apostle Paul wasn’t speaking to non-Believers in this passage.  Rather, he was directing the faithful to stop judging one another.  You probably know someone who has been deeply wounded at Church by some hyper-critical  Carnal Christian, and now because of that, has turned their back totally on Christianity and anything to do with God.  For them, they can only see hypocrisy in fellow Believers that should be showing the love of Jesus…but instead are negative and critical.  Such Carnal Christians are a hindrance and a barrier to the Gospel Message.