Does anyone know the meaning of the symbol on my grandfather’s grave?

Hi, everyone!

I only recently discovered the name of my grandfather last week, and from there I was able to find a picture of his grave online. On his grave, there is a symbol of a hand pouring water from a pitcher into another hand. I tried to google what this symbol means, and I found that a singular hand and pitcher indicates he was a Levite, but I couldn’t find anything for the specific version of it that has the additional hand. Thank you to anyone who can help!

Here is a picture of the gravestone: https://imgur.com/a/1NDXfSb

Also, quick note, my mother is unfortunately very assimilated. I’m a teenager who is trying to de-assimilate little by little, so if I come across as somewhat uneducated on these matters, that’s why!

Thanks again 🙂