Check out the Constitution and find where free speech depends upon the payment of taxes. Yes, I know that is current federal law regarding churches, but it is wrong, wrong, wrong! We even fund public radio and television with tax dollars; plus they certainly pay no taxes, and they weigh in on politics all the time. Furthermore, black churches engage in political speech freely, and leftwing churches engage in it disingenuously. Only traditional, largely white churches are held to the current federal standard.
Churches (and all pastors) should have the same free speech as any other entity in this country, whether or not the organizations pay any sort of taxes. There is no Constitutional justification for making free speech dependent upon the payment of any tax. The taxation excuse for muzzling others' free speech in this country is evil and disgusting!