Lama and Yama

Question from a non-linguist:
My pleasure reading of Oriental fiction and myth seem to frequently run into the words "Lama" and "Yama". The first usually refers to a holy man and the second to a God. Of course the words sound fairly similar to my ear. So I am curious: Are they were derived from a common origin?
I briefly poked around the internet and found nothing that was based on anything other than it sounded cute to say "Lama Yama" or "Yama Lama" three times quickly. Since I really don't know how to find the right hole to force a search engine into, I thought I'd try you all.
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Jeff Barnett