It is okay to bash Christ. That's what the world does to Jesus, it bashes Him. Jesus tells us to expect to be bashed for identifying ourselves with him. For following Him. There's no reason unbelievers shouldn't bash us. They don't have the Holy Spirit, so how can they be good? How can we ask them to be good when they don't have the Holy Spirit, and we know that even we can't be good without Him?
We should not be surprised, offended, or shocked when the world bashes Christians or Christ.
We should be more surprised when they do not bash us of Him.
We should not expect secular institutions such as television stations, stores, corporations, or government to act morally when they do not have the Holy Spirit.