ASK FATHER: Does 4th Commandment apply to in-laws?

From a reader…

I simply cannot find the answer to this anywhere. My understanding is that my father in law and mother in law are my parents under the Catholic Church and therefore the 4th commandment applies to my duties and obligations towards them just as it does towards my natural father and mother. There is a lot of information about a relationship between a brother in law and sister in law being incest, but I can’t find anything where Catholic teaching or Catholic saints write specifically about positive teachings in regards to a Catholic’s obligation towards his in-laws. Or am I wrong in assuming the equivalence between a parent and parent-in-law? If you could kindly point me towards a book or website that may have information about this that I could look up myself, that would be more than enough, but I would be grateful for any information about this topic.

ANSWER FROM Fr. Tim Ferguson (a frequent commentator here): 

The Catechism of the Catholic Church treats of this matter, somewhat, in paragraph 2199. This paragraph says,

“The fourth commandment is addressed expressly to children in their relationship to their father and mother, because this relationship is the most universal. It likewise concerns the ties of kinship between members of the extended family. It requires honor, affection, and gratitude toward elders and ancestors. Finally, it extends to the duties of pupils to teachers, employees to employers, subordinates to leaders, citizens to their country, and to those who administer or govern it. This commandment includes and presupposes the duties of parents, instructors, teachers, leaders, magistrates, those who govern, all who exercise authority over others or over a community of persons.”

While it doesn’t specifically mention in-laws, I think one’s obligation of respect toward them is spelled out in this paragraph.

Further, the Church places before us in Sacred Scripture the Book of Ruth, which tells the story of Ruth, who, after the death of her husband, follows her mother-in-law in the spirit of filial piety and for her fidelity is rewarded with a new husband, with whom she bears the grandfather of King David. The Church Fathers (particularly St. Ambrose, St. Jerome, and Origen) write about Ruth as a model of the Church and as a prefigurement, in the Old Testament, of salvation being offered to the Gentiles.

Lastly, Christ’s own obedience and respect toward his foster father, Joseph, while not in the same category as a father-in-law, gives us an example to follow of showing the respect that is due to all those who are in a position of authority as well as respect to our elders, be they our parents, parents-in-law, foster parents, or other older relations.

The moderation queue is ON.

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  1. Serviam says:

    If you think about it, since we are “one” with our spouse, then their parents are basically, by extension, our own….in a sense.

  2. Adaquano says:

    A good way to increase in the virtue of charity depending on the in-laws.

  3. jltuttle says:

    In-laws = moderation queue is On. That’s funny.

  4. The precept of charity dictates that it is so. It is especially the case–involving charity–when you consider that married couples must help one another toward heaven: Helping your spouse by being charitable toward his or her parents goes a long way to that end. In some cases we would even need to add the phrase “to be sure” somewhere in the last sentence.

  5. IloveJesus says:

    It’s good to remember at times that we owe them respect, not obedience.

    Some in-laws and parents even tend to forget this. ;)

  6. Imrahil says:

    Without the desire to contradict Fr Fergusons excellent answer, some musings:

    1. It would seem not to matter so much, practically speaking. That is, it matters if the sin is done and we go to the Confessional and want to name the specific commandments we broke; but as an actual guidance of what to do, we have to honor everyone in any case, relations or not, even as merely a necessary implication of loving one’s neighbor; now the in-laws certainly belong to “everyone”.

    2. It may be helpful to know that while one of the ways in which principally immature children have to honor their parents is obedience, as has been said, the thing is about not obedience, but honor. Honoring one’s parents may, for an adult, on occasion be compatible with disobedience.

    3. The answer to the question is “Yes, obviously”.

    4. Of course let’s go a bit back on no. 1: e. g., parents-in-law must be cared-for in their old-age, and generally speaking perhaps occasionally visited, just as well as parents (which one’s chance neighbor in the street wouldn’t be.)

  7. Justalurkingfool says:

    It will become even more interesting as biotechnology supplants the norm and there actually are multiple parents whose genetic materials give rise to children in increasing numbers and with use of purely synthetic components and even other species and plant components…..

    Mother Earth


  8. slainewe says:

    I really hate it when Holy Joseph is called the Lord’s “foster father.” A man is the real father of every child born of his valid wife, no matter the biological circumstances. Even the law supported this before the devil took over the courts. Today, “foster parent” refers to a paid caregiver, not even the child’s legal guardian.

    Our Lady’s virginity has been confirmed over and over these past 2000 years and engraved in the hearts of all faithful Catholics. It no longer seems necessary to impugn the fatherhood of the Blessed Virgin Joseph to protect Her perpetual virginity.

    When the Queen found Her Son in the Temple, She said to Him, “Thy FATHER and I have sought Thee.” Why qualify the word of Our Lady?

  9. Aquinas Gal says:

    Yes, respect, and care when needed when they are old. But certainly not obedience since adults are no longer children. Especially when the mother or father in law tries to meddle in their children’s marriage. This has been known to happen…

Comments are closed.