Sounds like the pastor is not bothering you but your brother-in-law and that seems to be bothering you.

Well, since you live in the USA, shooting him could be an option ?

Tell him to fuck off...pretty simple.

Tell him the truth. You've nothing to hide or be ashamed of.

Restraining Order

Tell him it is not any of his goddamn business.

A simple "no" should suffice.
If he persists, tell him you are an atheist.
Don't be afraid to be out.

You listen far too much to what your brother in law is saying. As soon as he opens his mouth you need to start thinking of what's for dinner, have you picket up the dry cleaning yet, do the kids need to go back to the dentist, etc, etc.

Clearly he doesn't know that he is the ex-pastor yet. You're welcome

stare at him and never respond when he speaks.

this works with exes, pastors, salesmen, anyone selling something. you're blank lack of response discourages them very quickly.

It is uncomfortable to be in any minority, particularly when it comes to belief systems. I am not you so take what I say with a grain of salt.
I would actually invite him to meet and tell him you no longer believe. He will liklely have much experience in "helping backsliders" and will have seemingly logical reasons to believe. He will likely try to guilt you into repenting.
The tact here is not to go with his talking points and just stick to "But I don't actually belive in there IS A GOD."
The test for a false god is that since there is no evidence said god requires faith. There is no god that does not require faith. Remeber this!

If he actually cares for you, you will know it. If he just wants to be right, or wants control it will also be obvious. It is only then that you can make the next move.

It sounds to me that he may only be conscerned about you. If so that os good even if his motives are misguided. He too like us is a human.

"I'm an atheist. Stop pressuring me about religion," works for me.

The truth will set you free from this pest !

OR ... you could have horns implanted on your head, and wear cat-eye contacts, with some blood smeared around your mouth, and try and mount him next time you see him...

So say "nice to see you. I am not looking for a church. Take care. Bye.

g

Put a statue of Baphomet in your front yard.

Then, everyone will leave you alone. Or they'll chase you out of town. Either way, problem solved.

Actually, that's terrible advice. Don't listen to me.

So long as the man is not threatening you or endangering you, then it's just a matter of time and he'll leave you alone.

That's when the rumors will start, though...

Where you don't want to out yourself yet - feel free to say "I'm doing just fine thanks for asking.". And leave it at that. (They can make their own presumptions).

Never give an answer to the question - simply deflect it.

Both your BIL and the former pastor should take the hint eventually.

You don't ever have to give an answer you don't want to give.

You can also go with "Oh I'm not concerned" and if that doesn't work "Neither should you be".

Try; "I've stopped going to church, if I'm ever interested again I'll let you know."
If that doesn't work try; "Feck off!"

Order of Protection or tell him you converted to Judaism.

"Yes, I have found the Satanic church, and I am happy to invite you to accompany me to a service."

I would use the best Brooklyn accent you can come up with and tell him you are going to make him an offer he can’t refuse and if the Brooklyn accent is too difficult to do I know a few people that would be glad to do it

If you have already made your decision that you no longer believe in god, then come out of the closet and be true to yourself. You don’t need to go around telling everyone that you no longer believe because it’s nobody’s business but yours. You don’t need share your belief (or disbelief to be more accurate), its a personal matter, but if asked directly I would just say that I no longer wish to go to church as I no longer believe in god. I think you will be relieved after you’ve done this, and won’t have this pastor on your case any more.

"nice to see you. i am not looking for a church and actually i consider religion something of a personal matter. thanks for caring. hope your day goes well. BYE."

g

What you describe sounds mild. I know someone who was hounded by the Mormons for decades. Even after they threatened legal action every year or so there’d be a call.