Often a distinction is made between liberal and conservative Christianity. I would make also make a different distinction - between "core Christianity" and "shell Christianity" (aka Churchianity). If you ever speak to a shell Christian, or read papers like the Daily Mail (and to a lesser extent the Daily Telegraph) you find out what is important to them - the externals. Dressing up in one's Sunday best, doing things "properly" etc.
For the paper this is very much The End Of Civilisation As We Know It.
The forebears of these witnesses would have trembled at the thought of lying on oath. For them, perjury was a dreadful weight on the conscience. For many today, "perjury" and "conscience" are empty words. The clear threat of prison if they are caught in falsehoods will have a far greater effect on them – but only if they seriously believe they will be found out. This is precisely why it will matter, if we cease to be a Christian country. Conscience, reinforced by religion, reaches into the secret corners where CCTV is blind, and DNA testing useless. It is particularly good at restraining those crimes which are hard to detect and hard to prove. Do we really want this to be a society where outward threats must increasingly replace inward self-control?
Reading that it feels like God is reduced to being a bogeyperson in the sky.
It is actually possible to be an atheist and have a conscience.
Having a conscience, a moral sense of right and wrong, is part of what being made in the image of God includes.
If we open up the Bible, rather than keep it as a closed book to swear oaths on, we see Jesus' command in the Sermon on the Mount:
“Again you have heard that it was said to those of old, ‘You shall not swear falsely, but shall perform to the Lord what you have sworn.’ But I say to you, Do not take an oath at all, either by Heaven, for it is the throne of God, or by the Earth, for it is His footstool, or by Jerusalem, for it is the city of the great King. And do not take an oath by your head, for you cannot make one hair white or black. Let what you say be simply ‘Yes’ or ‘No’; anything more than this comes from evil." (Matt. 5:33-37)