I go to court with my clients every week. I see the swearing in every time. I always thought it was swearing to God. But... Now I understand that it is swearing or affirming. Swearing to God... or affirming to truth if not religious.

They need to change it from the book of lies to the dictionary a book of knowledge. Omit the deity part and add to On my freedom.

I believe you have the right to ask for a secular swearing in question that does not mention any god. Maybe Google knows????

I think that you can affirm that you are telling the truth.
Certainly can in the UK, probably varies by state here.