From Wikipedia:
In the US, people can use either "so help you God" or "under pains and penalties of perjury"; all oaths and affirmations are considered equivalent before the law.[14] These modifications to the oath were originally introduced in order to accommodate those who feel uncomfortable swearing religious oaths, such as Quakers, as well as to accommodate the irreligious.[15] In United States v. Ward, the Ninth Circuit Court of Appeals ruled that certain other modifications of the oath were acceptable so long as they demonstrated "a moral or ethical sense of right and wrong".[16]

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

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????