The Alvars and Nayanars initiated a movement of protest against the caste system and the dominance of Brahmanas. This is evidenced by the fact that bhaktas hailed from diverse social backgrounds, ranging from Brahmanas to artisans, cultivators, and even castes considered "untouchable".

They challenged the Brahmanical monopoly over sacred knowledge. The Nalayira Divyaprabandham, a major anthology of Alvar compositions, was described as the Tamil Veda, claiming equal significance to the four Vedas in Sanskrit cherished by Brahmanas.

The Alvar saint Tondaradippodi, a Brahmana himself, expressed a sharp critique by stating that Vishnu prefers "servants" who express love for his feet, even if born as outcastes, over Chaturvedins (Brahmanas versed in the four Vedas) who lack devotion. This directly questioned caste-based privileges.

The Virashaivas or Lingayats offered a more radical critique by challenging the very idea of caste and the "pollution" attributed to certain groups by Brahmanas. They also questioned the theory of rebirth.

Additionally, the Lingayats encouraged practices disapproved in the Dharmashastras, such as post-puberty marriage and the remarriage of widows. These critiques, expressed through their vachanas in Kannada, won them followers among those marginalised within the Brahmanical social order.