Take an oath: what does that mean? (Based on natural by imagine dragons)

I was listening to a song by imagine dragons called natural. It's a song that came out earlier this year and I've liked it since the first time I heard it. Anyway, what made me bring that song up is the expression "to take an oath".

If you've heard of that expression before, this post is going to get easy for you from now on. That's because I'm going to try to explain the meaning of it.

When you take an oath or make an oath, you make a formal, binding promise; you swear to something. For example, when you become a witness in court, you're told to take an oath that you will always tell the truth.

The song goes like "took an oath by the blood on my hand". That's a more specific kind of promise. The one that involves blood in it, the blood oath. It's easy to think of two people taking a blood oath by cutting their own hands and shaking them together, or even licking each other's blood. Yeah that's gross.

The good thing is that you don't have to be so gross to use that expression. When you take an oath, you simply make a promise. It might be a formal one, but still a promise. You can use that expression to refer to the act of making a regular promise, but it's not the way people say it regularly. So maybe you wanna be funny or dramatic.

That's all for now. Talk later