[Invocation]. I'm kidding!

>You changed your message. You said that this greeting was used in socialist countries and that this is an indication it's not religious. I am asking you to tell me which countries did you mean and why it's an indication.

this is realy not important

>E.g. do you mean that if something is used in socialist countries it automatically disqualifies the religious context?

no.

It's just an example how ridiculous it is to me. As stated before:

A wish or a greeting should be handled as such to the first. A friendly, peace making gesture.
Only if the greeter knows by fact that the other side is affronted, this will change.

We have here the problem that bavarians commonly greet with "Grüß Gott" (God greets you). They mean normaly nothing with it - it offends me and a lot easterners anyway.
The normal answer would be the same - but trust me, I would swallow my tongue first. But, this is my POV in this conversation. I can simply not say this - due to my believes. This - the response necessary is offending me. That has nothing to do with my respect to somebody else.
So one have to find a friendly response - what else? Normaly one tries to do a friendly joke one a pun possible on this greeting. It gives the greeter a chance to laugh - and understand the problem that he does something that is strange to me. German lang allows greetings free of religious context.

This is far away to pouring endless passages of books in a forum - and there was a lot tolerance and a tons of friendly clues here. I'm sure it will not change on this singularity.

You got me? If not, I trust on your tolerance.