I don’t believe in religious exceptions to the law, or that religious belief deserves special treatment over non-religious belief.

Traditionally the Sherbert test from Sherbert v. Werner determines if a 1st amendment infringement to free exercise is at play.

The Sherbert test has three parts.

One is if the government is burdening the individual to give up free exercise. A good example is providing a penalty for activities that would force one to give up one's religious practices.

Even given that, there is a compelling interest exception. But that would have to pass, I think, a rational basis test. To show that the infringement is related to compelling state interest. If not it would be an infringement by point #1 of the Sherbert test.

And the third is a narrow tailoring exception. Basically no other legislation in the public interest will fail to infringe, so we have to accept that for the moment.

So on the first prong of the Sherbert test is the question of how getting vaccinated infringes on one's religious practice. Compulsory vaccination would also seem to fit under the second and third prongs too. We're not getting polio back dog, so this is how it is...