On the first link you provided the piece is identified as a scene of "hierogamy".
I looked it up and found this:
8. What is "hierogamy"?
"Hierogamy" comes from the Greek word "hieros" which means "sacred" and from "gamos" which means "marriage". Although according to esoteric doctrine, it refers to marriage to the Lord's Anointed, it can be applied, generally, to all Christians who enter into the kind of marriage which is sanctified by the Bride/Bridegroom typology of the Bible.
Principally, hierogamy is a symbolic (or platonic) marriage which focuses on the unity of soul which is manifested in the Blessed Trinity and which is meant to be imaged in the earthly family.
Hierogamy comes from a custom of the Early Church which required the bishop to be "a husband to the widow, and father to the fatherless". As Christ's representative, he was their "kinsman-redeemer" (see the book of Ruth)."
The above scene appears to me to be an older man straddled by a younger man, with another man standing behind. Or are the circles on the chest signifying breasts?
Your second link says:
Divine Marriage
Sexual union between the goddess daughter and the hero son. The mother of the gods stands beside them.
Interesting....Must be breasts!
The picture shows two women and one man.
The first woman (left) carries two symbols; 1) A vase, and 2) a serpent.
The second woman - backed by the first woman - is occupied in a coitus with the man.
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The image - created during Roman antiquity - is associated with parallel phrases known from the antique period of Greece known as "hieros gamos" and thus translated to our concept of "a divine marriage".
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The image catches this very moment of creation, explaining the old (pagan) custom of sharing the "female power" as it manifests through her sexual liquids. According to the Finnish saga-material there would be a row of sisters and other female "heart-friends" that would "line up" to share their female essence ("sav") into the same vas(e) - before it was brought to the woman presently elected to reproduce. The tradition explains that this contribution - of "all the lotus-sisters" - was seen as an (w)holy act in itself.
The female serpent is referred to as a symbol of that collective contribution. The content of the vase is also described as "holy" - as in "holy water", "well water" and "water of life" - as well as "sav".
The idea was that this elixir contains the very best of nourishment for the vital and revitalizing body-functions of the female body. Thus the well of this water was also known as the "fountain of youth".
The legend of "The Seven Sisters" tells more explicitly about how seven daughters thanked their father by supporting the spouse ("Swan") elected for his procreating son ("Balder") - their brother. Some sisters-in-law to get...!
When The First Family of the population (culture) - commonly called The Royals - were about to initiate a new generation of successors it was custom that all the local women were involved in a sharing that was collected - via "Ternor", "Nornor" and "Vùlvor" - to the duchess and 7 princesses sisters - collecting a reflection of the genetic dynamics and strength of the entire female population - as a common contrbution to the new queens offsprings; the next generation of the countries oldest - and thus first - family-line, from where all the other descends...
A parallel system is seen with the male serpents and their carriers of cups and grals...