✝O3 The Priestly Puzzle

What connections, if any, are there between the priesthood of Judaism and the priesthood of early Christianity?

IMAGE CREDIT:

Photograph of medieval canvas "Abraham and Melchisedek"

Dieric Bouts,the older. At The Church of Saint Peter, Leuven, Belgium - http://www.heiligenlexikon.de/Fotos/Abraham-Melchisedek.jpg
"Ökumenisches Heiligenlexikon" (URL: http://www.heiligenlexikon.de) released this JPEG picture into the public domain, which can be checked on http://www.heiligenlexikon.de/BiographienA/Abraham.htm.