He was not on company time and he did not identify himself as an employee of Allstate yet he was fired for expressing a political and religious view. Looks like his right to free speech and religion and freedom of association were violated to me.
Well, then you should really familiarize yourself with the Bill of Rights. The First Amendment offers no protection whatsoever against the actions of private entities, businesses or individuals.
And, while he may not have identified himself as an employee of Allstate, the publication did. In the end, that publication may have screwed him unintentionally.
No, no, no. You have a right to free speech, and you have your right to your freedom of religion, but those rights don't preclude PRIVATE repurcussions. You might lose friends, and other voluntary associations over your views. The constitution was never meant to protect you from that.