Here are three quotes in the Vedic Samhitas:
ब्रा॒ह्म॒णो॑ऽस्य॒ मुख॑मासीद्बा॒हू रा॑ज॒न्यः॑ कृ॒तः ।
ऊ॒रू तद॑स्य॒ यद्वैश्यः॑ प॒द्भ्यां शू॒द्रो अ॑जायत ॥ १०.०९०.१२
The Brahman was his mouth, of both his arms was the Rajanya made. His
thighs became the Vaisya, from his feet the Sudras was produced. ~Rig Veda 10.90.12 translated by R. Griffiths
Yajur Veda 26.2 translated by Devi Chand:
I do hereby address this salutary speech for the benefit of humanity,
for the Brahmanas, the Kshatriyas, the Sudras, the Vaishas, the
kinfolk and the men of the lowest position in society.
Yajur Veda 18.48 translated by Devi Chand:
O God grant love to our holy priests, set love in our ruling chiefs.
Grant love to the Vaishyas and Shudras; give out of Thy unbounded
store of love, love unto me!
Let me add that the caste system as seen in certain Smritis is not seen in the Vedic Samhitas.
If then with all the documents before us, we ask the question, does
caste as we find it in Manu and at the present day, form part of the
most ancient religious teaching of the Vedas? We can answer with a
decided No. ~Max Mueller in Chips from a German Work-shop
Moreover the hereditary caste system is invalid because it violates the guidelines given in Hindu scriptures on ground of discrimination against a large group of people. The guidelines are given below.
Guidelines
Everything written in Hindu scripture is not valid. A scriptural statement can be invalid if it does not satisfy reason.
Primacy of reason
Bhishma Said:
Even the words heard from an ignorant person, if in themselves they be
fraught with sense, come to be regarded as pious and wise. In days of
old, Usanas said unto the Daityas this truth, which should remove all
doubts, that scriptures are no scriptures if they cannot stand the
test of reason.
Mahabharata Shanti Parva Section CXLII
Acharya Shankara says:
The appeal to the infallibility of the Vedic injunction is
misconceived. The infallibility in question refers only to the unseen
forces or apurva, and is admissible only in regards to matters not
confined to the sphere of direct perceptions, etc ... Even a hundred
statements of sruti to the effect that fire is cold and non-luminous
won't prove valid. If it does make such a statement, its import will
have to be interpreted differently. Otherwise, validity won't attach
to it. Nothing in conflict with the means of valid cognition or with
its own statements may be imputed to sruti.
REF: Srimad Bhagavad Gita Bhasya 18.66 of Sri Sankaracarya translation by Dr. A. G. Krishna Warrier, p. 629.
Rejection of discriminatory verses
Any discriminatory verse in Hindu scripture is also automatically invalid according to Hindu scripture and should not be followed. This is necessary because Hinduism is not an organized dharma and does not have any central body to oversee the content of Hindu spiritual texts.
If a holy act is against the interest of other members of the society,
it should not be practiced. It is Dharma which is the source of Artha
and even of Kama.
Kurma Purana I.2.54