Suspect wiring for sconces

Question

I am replacing two sconces that are over my mantle in a 1930s house. The strange thing is that one sconce had two of each wire going to it. Can this cause a problem? Is there any reason to do this assuming that just two wires would be enough to support the sconce? If I should be using both wires I suspect a pigtail would be the proper way to do this these days (although not as easy with this old wiring as it’s not very malleable)?

Here is the box with just the two wires:

And the box with the four wires:

Any guidance here would be greatly appreciated!

Answer 1

I think I've figured out what this is - I imagine there have been sconces here for quite some time (although the ones I removed were more recently updated). I'm guessing these wires were simply extended to the other sconce where there are only two wires - basically this was the older version of what today you would solve with a pigtail. Assuming the new sconces have wire leads I should be able to just couple them in here with a yellow cap.