Scriptural source for the Subhāṣita that says 'treat others' wives as your mother'

Question

The other day I was listening to a discourse on Rāmāyaṇa ^‡ where the speaker points out that although it is very simple for anyone to say सत्यं वद । धर्मं चर ॥ ^§ (Speak truth, follow dharma.), but when you are walking on the street one day and suddenly face a difficult situation, you will not be carrying with you the various smṛtis and dharma śāstras to immediately refer to and take the most dhārmic decision and, even if you did carry them, you will not have the time to quickly go through them to determine the correct way of doing something. So our great Ṛṣis have condensed the entire dharma for everyone to follow into three simple formulas:

1. Train your mind to look at or treat every woman that you encounter in your life who's not your wife as your own mother.

   • E.g., if you happen to notice a pretty lady (or person of opposite sex) in your circle of friends or relatives, at work etc. you will treat the person as your mother, father or your iṣṭa-devatā – this should cut down any temptation you may yield to.

2. Any wealth or property that is not yours, treat it like dirt.

   • E.g., if you were to find a gold chain on the street you'd simply ignore it's even there. If you did pick it up, you'll try to locate the owner of the jewelry but not keep it for yourself. If you follow this rule, you'll also not accumulate black money, default on a loan etc.

3. Show sympathy and compassion to every living being.

   • E.g., if you feel like hitting a street dog with a stone, imagine someone throwing the same stone at you.

I thought the speaker was actually referring to the Vedas, Upaniṣads or Itihāsas but was disappointed to learn he was simply quoting the following Subhāṣita.

From here:

मातृवत् परदारांश्च परद्रव्याणि लोष्टवत् ।
आत्मवत् सर्वभूतानि यः पश्यति स पश्यति ॥

- समयोचितपद्यमालिका

mAtRuvat paradArAmshcha paradravyANi loShTavat ।
Atmavat sarvabhUtAni yaH pashyati sa pashyati ॥

- samayochitapadyamAlikA

The right way to look at other people's wives is as if she is your mother, other people's wealth as if it is lump of mud, all other beings as if they were you.

- Samayochitapadyamalika

A slightly different one from here:

मातृवत्परदारेषु परद्रव्येषु लोष्ठवत् ।
आत्मवत्सर्वभूतेषु यः पश्यति स पण्डितः ॥

– हितोपदेश, सन्धि

A wise man will treat other people's wives as his own mother. He treats other people’s wealth as a lump of mud (stone). He will treat every being in this world with compassion as he would treat himself.

– Hitopadesha, Sandhi

Question:

Do any of our scriptures convey the same message as the Subhāṣita above? If so, can you cite the relevant verses and their translation?

^‡ _{Link to YouTube video (Telugu) by Sri Chaganti Koteswara Rao}
^§ _{Taittirīya Upaniṣad 1.11}

Answer 1

Another man's wife is ideally to be treated as one's sister.This is what the following verse suggests:

Manu Smriti 2.129. But to a female who is the wife of another man, and not a blood-relation, he must say, ’Lady’(bhavati) or ’Beloved sister!

Now, the Scriptures also say that an elder sister is to be treated like one's mother,although the mother is more venerable among the two.

Manu Smriti 2.133. Towards a sister of one’s father and of one’s mother, and towards one’s own elder sister, one must behave as towards one’s mother; (but) the mother is more venerable than they.

So,treating another man's wife as one's own sister or even as one's own mother both are correct.

Update- This Brahma Purana chapter describes Sadachara(Right conduct) :

Here Sri Vyasa quotes Parama Shiva on how to differentiate between Dharma and Adharma as follows:

Dharmaadharma Nirupana(Determination of Dharma & Adharma):

Parama Shiva further delineated to Devi Parvati about those who had Trikarana Shuddhi, Indriya Nigraha, and Ahimsaacharana (Clealiness of Body-Mind-Heart; Control of Senses and Non-Violence).

They are eligible to Swarga if they had no desire for other’s money except for one’s own well earned; if they did not react to other women except one’s own lawful wife while treating truly and heartily the others as his mothers, sisters and daughters; if they serve all the Beings with fellow- feelings of warmth and consideration; if they would hurt none directly or indirectly by way of speech, thought or action;

@SV the highlighted quotes above are the closest i could find from either Smritis or Puranas that match with the import of the Subhasitas given in your question.

Answer 2

The Manusmriti verse 2.129 has a similair verse venerating other man's wifes:

परपत्नी तु या स्त्री स्यादसम्बन्धा च योनितः ।
तां ब्रूयाद् भवतीत्येवं सुभगे भगिनीति च ॥ १२९ ॥

parapatnī tu yā strī syādasambandhā ca yonitaḥ |
tāṃ brūyād bhavatītyevaṃ subhage bhaginīti ca || 129 ||

A female who is the wife of another person, and is not related to one by birth, should be addressed as “Lady,” and also “blessed,” or “sister.”—(129)

Commentary by Medhātithi:

If the lady happens to he an elderly one, she should he addressed as ‘mother,’ ‘glorious one’ and so forth; and if she is younger in age, she is to be addressed as ‘daughter,’ ‘long-lived one,’ and so forth.

And another (verse 2.145) venerating the mother:

उपाध्यायान् दशाचार्य आचार्याणां शतं पिता ।
सहस्रं तु पितॄन् माता गौरवेणातिरिच्यते ॥ १४५ ॥

upādhyāyān daśācārya ācāryāṇāṃ śataṃ pitā |
sahasraṃ tu pitṝn mātā gauraveṇātiricyate || 145 ||

In veneration, the Preceptor excels ten Sub-teachers; the Father a hundred preceptors, and the Mother a thousand Fathers.—(145)

And the Vishnu Smriti verse 32.7 has another similair verse as well:

"To the wife of another, even though he does not know her, he must either say 'sister' (if she is of equal age with himself), or 'daughter' (if she is younger than himself), or 'mother' (if she is older than himself)."

Answer 3

We have an exact verbatim verse in the [Bṛhaspati (Nītisāra) Saṃhitā of the] Garuḍa-Purāṇa (Verse 12, Chapter 111), that exactly says what is asked in the question.

Garuḍa-Purāṇam => ācārakāṇḍaḥ

Chapter CXI

मातृवत्परदारेषु परद्रव्येषु लोष्टवत् ।
आत्मवत्सर्वभूतेषु यः पश्यति स पण्डितः ॥ १,१११.१२ ॥

12. He, who looks at another’s wife as his own mother, at another’s goods as (worthless) brickbats, and upon all men as similarly susceptible to impressions of pleasure and pain as his own self, sees but right.

English Translation by M.N. Dutt

So, afterall, the Speaker was Quoting from a Mahā-Purāṇa only, and the exact same verse is found in the Hitopadesha too, as quoted in the question.