अन्ध स्थान्धो वो भक्षीय मह स्थ महो वो भक्षीयोर्ज स्थोर्जं वो भक्षीय रायस्पोष स्थ रायस्पोषं वो भक्षीय ।। यजु-3-20
andha sthāndho vo bhakṣīya maha stha maho vo bhakṣīyorja sthorjaṃ vo bhakṣīya rāyaspoṣa stha rāyaspoṣaṃ vo bhakṣīya || yaju-3-20 

Meaning – You are the provider of the most desirable objects. The most desirable first for human beings is our food that provides sustainable energy for our joys, well-being & prosperity and you are the provider of all. Also,

रेवती रमध्वमस्मिन्योनावस्मिन्गोवेऽस्मिंल्लोकेऽस्मिन् क्षये । इहैवस्त मापगात।। यजु 3-21
revatī ramadhvamasminyonāvasmingoveasmiṃllokeasmin kṣaye | ihaivasta māpagāta|| yaju 3-21

Meaning – You are the embodiment of entire desirable wealth in this world, on our lands & in our homes. Live here, with our love and peace; never go far from us.

संहितासि विश्वरू प्यूर्जा माविश गौपत्येन। उपत्वाग्ने दिवे दिवे दोषावस्तर्ध्दिया वयम्‌। नमो भरन्त एमसि ।। यजुर्वेद 3.22. 
saṃhitāsi viśvarū pyūrjā māviśa gaupatyena| upatvāgne dive dive doṣāvastardhdiyā vayam‌| namo bharanta emasi || yajurveda 3.22.  

Meaning – Cows have the same importance to the world as Vedas. The cows are responsible for the beautiful glow of brilliance and energy of the world. Day by day growing bounties in the world flow from the cows. We pay homage to such bountiful cows.

The Vedas have distinctly established the importance of cows in poverty alleviation and social stability.

ऋषि – कृष्ण अंगिरस इन्द्रो देवता गोभिष्टरेमामतिं दुरेवां यवेन क्षुधं पुरुहूत विश्वाम्‌।वयं राजभिः प्रथमा धनान्यस्माकेन वृजनेना जयेम।। (1.1.0a ऋ 10.42.10, 10.43.10, 10.44.10. अथर्व 7.50.7, 20.17.10, 20.89.10, 20.94.10).
ṛiṣhi – kṛiṣhṇa aṃgirasa indro devatā gobhiṣṭaremāmatiṃ durevāṃ yavena kṣudhaṃ puruhūta viśvām‌| vayaṃ rājabhiḥ prathamā dhanānyasmākena vṛjanenā jayema|| (1.1.0a ṛ 10.42.10, 10.43.10, 10.44.10. atharva 7.50.7, 20.17.10, 20.89.10, 20.94.10).

Meaning – Lord Krishna is the seer Rishi of this Ved Mantra. It is unique that this mantra is repeated seven times in Vedas, three times in Rig Veda & four times in Atharva Veda. This implies the importance the Lord gave to Cows for the welfare and prosperity of human society. The message in this mantra is,

1. Total poverty results from the total absence of knowledge/awareness/education in people. They fall in bad ways.,

Remedy for this situation by Gopalan: 

1. Taking care of cows (Modern strategists also agree that animal husbandry is the only viable method of poverty alleviation for the poorest deprived people)
2. Grow barley etc. (Organic crops) to feed the hungry in the world. (Experts all over the world agree that only Organic Agriculture can sustain the world ecologically, and for this cow is the critical link.) 
3. The removal of poverty, ignorance & hunger from the world, will at first make the individual prosperous, which in turn will make the state/society rich. Only then, the devious elements in society will become vanquished successfully. 

From time immemorial, the cow is regarded as ‘the sacred mother’ and has the name Kamadhenu (bestower of every wish). Rigveda states that ‘Cow is truly our mother.’

माता रूद्राणां दुहिता वसूनां स्वसादित्यानाममृतस्य नाभि:। प्रनु वोचं चिकितुषे जनाय मा गामनागामदिति वधिष्ट।। RV 8.101.15
mātā rūdrāṇāṃ duhitā vasūnāṃ svasādityānāmamṛtasya nābhi:| pranu vochaṃ chikituṣe janāya mā gāmanāgāmaditi vadhiṣṭa|| RV 8.101.15

Mother of Rudra, daughter of Vasus & sister like the very breath of the Sun, a cow is truly the divine fountain from which Devtas nectar emerges for amazing splendor of mankind. Hence, do not kill a cow that is not to be killed at all. 

Rigveda also mentions that, 

वचो विदं वाचमुदीरयन्तीं विश्वाभिर्घीभिरुपतिष्ठमानाम्‌। देवी देवभ्य: पर्येयुषी गा मा मावृक्त मर्त्यो दभ्रचेता।। RV 8.101.16.
vacho vidaṃ vāchamudīrayantīṃ viśvābhirghībhirupatiṣṭhamānām‌| devī devabhya: paryeyuṣī gā mā māvṛkta martyo dabhracetā|| RV 8.101.16. 

Cow imparts the faculties of speech with good intellect and knowledge. Cow establishes the intellectual capacities for the expression of positive sustainable, most beautiful strategies. Members of society develop divine qualities and wisdom to lead a loving and peaceful life, & achieve a sustainable ecosystem. Only the unintelligent man neglects the cows. Cows enrich us day by day. 

सुरूपकृत्नुमूतये सुदुधामिव गोदुहे। जुहूमसि द्यवि द्यवि ।। RV 1.4.1 ऋ 1.4.1
surūpakṛtnumūtaye sududhāmiva goduhe| juhūmasi dyavi dyavi || RV 1.4.1 ṛ 1.4.1

Daily efforts in service of good milk-giving cows bless us with beautiful bounties.

उप नः सवनागहि सोमस्य सोमपाः पिब । गोदा इद्रेवतोमदः ।। ऋ 1.4.2
upa naḥ savanāgahi somasya somapāḥ piba | godā idrevatomadaḥ || ṛ 1.4.2

Cows are knowledge enhancers 

गौवों से दिव्य चक्षु मिलते हैं, गौ पालन से पुरुषार्थी स्वभाव बनता है, जो सुख और संपन्नता लाता है। RV 1.8. 8
gauvoṃ se divya chakṣu milate haiṃ, gau pālana se puruṣārthī svabhāva banatā hai, jo sukha aura saṃpannatā lātā hai| RV 1.8. 8 

Cows give visions to make knowledge-building hubs that increase our knowledge resources, making us more enterprising to be prosperous & happy.

गौ सम्पदा से समाज को प्रभावशाली नेत्रित्व मिलता है एवा ह्यस्यसूनृता विरप्शी गोमती मही। पक्वा शाखा न दाशुषे ।। RV 1.8.8
gau sampadā se samāja ko prabhāvaśālī netritva milatā hai evā hyasyasūnṛtā virapśī gomatī mahī| pakvā śākhā na dāśuṣe || RV 1.8.8

Good Cows brings forth good leadership

 गौ सम्पदा से समाज में ओजस्वी वाणी वाला नेत्रित्व उत्पन्न होता है जैसे वृक्ष पर पके फल मिलते हैं। AV 6-45-1
gau sampadā se samāja meṃ ojasvī vāṇī vālā netritva utpanna hotā hai jaise vṛkṣa par pake phal milte haiṃ| aV 6-45-1 

Land with an abundance of good cows, develop forceful speakers and good statesmen, like fruit trees bearing ripe fruits in plenty.

परोऽपेहि मनस्पाप किमशस्तानि शंससि ।परेहि न त्वा कायये वृक्षान् वनानि सं चर गृहेषु गोषु मे मनः ।। अथर्व 6-45-2
paro’pehi manaspāpa kimaśastāni śaṃsasi |parehi na tvā kāyaye vṛkṣān vanāni saṃ chara gṛheṣu goṣu me manaḥ || atharva 6-45-2

Cow shields from bad thoughts.

Lord Krishna states in Srimad Bhagavad-Gita: chapter 10, verse 28, that ‘dhenunam asmi kamadhuk’ – Among cows, I am the wish-fulfilling cow. Wherever cows live, that is his place. 

Science of Vedas, consider the greatness of the cow as all-round in nature. Compared to the entire universe, the cow is considered a God – “Yetad ve viswaroopam sarvaroopam go roopam.” Atharvaveda 9-7-25.