I just say, "Thanks"

They only usually say this after they have no more arguments and are threatening to have their god step in and forcibly change my mind, so I ask why it was five minutes ago they were all for free will and want god to brainwash me.
At this point they will say no, that's not it, so I ask just what they are praying for me for? They never have an answer.
Or I ask does anything happen that is not in gods plan when they inevitably say no, I point out god then must want me to be an atheist and is it not presumptuous to disagree with god. On the one occasion when some one said yes, I gleefully followed up with pointing out that god was therefore not all powerful in their opinion and that saying such was blasphemy

I say thank you. And leave it at that.

Why would you do otherwise? They aren't do you any harm by saying or doing that. Good for you for being a civil adult.

Hmm! If you like.

That line usually follows some insight they gain about your "poor, pitiful condition" as an atheist/non-religious type (of THEIR religion, right?). It's a dismissal in my opinion, and generally shuts the door to any further discourse. When religious folk run into a wall, this line comes out of the closet.
Because that's the case for the most part, my response is generally a smile with "thank you for appreciating who I am" and then depart.
One cannot counter that line with any logic or opportunity for critical thinking because the speaker has stated their position as above you because in their mind, being religious (of THEIR religion) is the only way to be a good person.

I say, "Thank you," and then change the subject.