When you hear something you've never heard before, watch out!

First of all, you might be hearing something extra-Biblical, made up by man even if they are claiming it is Biblical. Reject it as contrary to scripture.

However... another reason it might sound new is just because you never were taught it. It might actually be Biblical but the tradition you are immersed in kept you from seeing it. 

Let God be true and every man a liar! (see Romans 3:4)