Old Testament the natural nation would become kings and priests. New Testament this would be Spiritual and extended to all the faithful.

Jesus was related to John The Baptist(alternate High Priest) through His maternal line and inherited BOTH royalty and priesthood when the elder priest was executed.

Adam had his side opened(cell split) and an X chromosome removed to make Eve(nothing to do with Baphomet crown Cabalah Tree heinous insanity created by fake-yoo ancient Satanist pagans who didn't understand cell biology) Adam was, in a sense, father of Eve and there is an alternate patrilineal line which alternates between males and females.