Absorb is the easier word to clarify. Think of drying yourself with a wet towel.
The American Heritage College Dictionary, Fourth Edition: absorb is “1.To take (something) in through or as through pores or interstices.” The Divine Jesus is pure spirit without material anatomical pores, described as "a minute opening in tissue; therefore, absorb is automatically ruled out.
For assume, from the above dictionary: 1. To take upon oneself:
assume responsibility. 4. To put on: don.
Google gave me:
3.
the disease may assume epidemic proportions
acquire, take on, come to have
4.
they are to assume more responsibility
accept,
shoulder, bear,
undertake, take on/up, manage, handle,
deal with
oxforddictionaries.com/us/definition/american_english-thesaurus/assume
and this definition from
thefreedictionary.com/assume
**3. ****a. **To take on (an appearance, role, or form, for example); adopt: “The god assumes a human form” (John Ruskin).
Google supplied this interesting thought about human nature.
en.wikipedia.org/wiki/Human_nature
Human nature refers to the distinguishing characteristics—including ways of
thinking,
feeling and
acting— which
humans tend to have
naturally, independently of the influence of
culture.
What I am finding from the above is that assume sounds somewhat close to absorb; yet, it is completely different from a towel accepting water and becoming totally wet. “Totally” is the operative word.
Obviously, I checked the *Catechism of the Catholic Church, Second Edition.
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*
If you have an hour or two, tackle paragraphs 456-478, including the cross-references in the margins. Or go to “In Brief” paragraphs 479-483.
This granny considers that the main point is that the Second Person of the Blessed Trinity did not lose His divine nature. His divine nature did not change in any way. There is an unique, one of a kind, union of both the divine and human natures in the one Divine Person, Jesus Christ. His divine nature did not become wet.
Regarding the question –
“Has human nature ever been “absorbed” by any being according to Catholicism?”
Answer. I hope not. I have had enough Google for this year.
Technically, God is a supernatural transcendent pure spirit Divine Being. Jesus as True God did not absorb human nature. As for all those creatures in the first chapter of Genesis, including our first parents, their nature is complete as is. Thus, the answer according to Catholicism is that “human nature” has never been absorbed by any being. Humans do not need to additionally absorb what they already have at conception.
Links to the
Catechism of the Catholic Church, Second Edition.
Enjoy!
usccb.org/beliefs-and-teachings/what-we-believe/catechism/catechism-of-the-catholic-church/
scborromeo.org/ccc.htm