One verse

Srimad Bhagavatam 3.12.41

3.12.41

विद्या दानं तप: सत्यं धर्मस्येति पदानि च । आश्रमांश्च यथासंख्यमसृजत्सह वृत्तिभि: ॥ ४१ ॥

vidya danam tapah satyam dharmasyeti padani ca asramams ca yatha-sankhyam asrjat saha vrttibhih

vidya
education
danam
charity
tapah
penance
satyam
truth
dharmasya
of religion
iti
thus
padani
four legs
ca
also
asraman
orders of life
ca
also
yatha
as they are
sankhyam
in number
asrjat
created
saha
along with
vrttibhih
by vocations.

Education, charity, penance and truth are said to be the four legs of religion, and to learn this there are four orders of life with different classifications of castes according to vocation. Brahma created all these in systematic order.