Let me ad some more thoughts and questions.
I shall let you know that I have not only a philosophical interest in these kinds of debates but also interest in practical nature.
A friend of mine died yesterday and that brought me back to questions of faith and how I perceived the situation.

For it to sound completely different in my ears, God would have to be real to my mind. But He, or She, or It isn't, so it sounds the same as "May the wrath of Gandalf descend upon me if I break this promise!" See how that works? I really have no problem with it sounding completely different to you though, you're welcome to your beliefs, I mean that.

It seems to me that you are somewhat holding back your understanding. Let me give you another example that will hopefully make it clearer what I mean when I say something "sounds" different from something else. If you include the context, for example.

You have a congregation sitting in church and they are gathering "in spirit". So it sounds different than if I say people are gathering "in a certain mood". There is a difference between "mood" and "spirit". "Mood" is a term you can use in every day life in different situations. "Spirit" is more reserved for religious matters.

When I say "I will love and honour you until death do us part", it sounds different from when I say "I promise not to part from you". Especially as I asked whether anyone even says the latter these days. When I say, "I swear by God to be faithful to you", this is meant as a reinforcer, that I am not just referring to myself, but to a fortifying source, known by others.

How can it sound the same to your ears when "the wrath of Gandalf" is not based on a two-thousand-year history of Christianity, i.e. not even remotely connected to the existing faith of people? In the context of people coming together in situations that are real for them, where they pray and sing together, for example at funerals, they need a common vocabulary.

However you talk to yourself alone, whether in thought or in words, you can substitute anything for "God" and feel something meaningful for yourself. You even might not see the need to pray or contemplate.

But the moment several people come together and want to do this in a common spirit, they inevitably need a commonly accepted form of expression.

Birth, marriage and death are recognised as the most important milestones in people's lives.
An important aspect of all these real events is that people are witnesses to each other when a child is born and baptised, when two people make a marriage vow and when someone dies. Marriage is not just about an intimate act between a man and a woman, but also about them making their covenant in front of witnesses. The more people witness this and are present, the more difficult it will be for the couple to separate afterwards for reasons other than very serious ones.

However, if it is the case that these acts mean nothing to anyone and the gathering in spirit is accepted as something that can be dispensed with, I personally consider this to be problematic and at the heart of many personal as well as societal conflicts in result.

In one respect, for example, this is made clear by Buddhist doctrine, which divides itself into three parts: Buddha, Dharma and Sangha.
Buddha is the ideal guiding figure, Dharma is the complete teaching and Sangha is the practice of coming together.

My question would then be: Do you think that any religion is dispensable and not needed? Or do you say that it only is dispensable for you yourself and it is just you who don't need it? If so, how do you prepare yourself in the face of death and how would you organize a funeral and honor a diseased one?