Kevalin is a conceptual term in Jainism. As per Jain philosophy, arhat siddhas, buddhas, and jivanmuktas are regarded as omniscient. However, in Jainism, a kevalin is one who is characterized by the Catustayas (four exemplary qualities) of anantha jnana (infinite knowledge), ananta darshana (infinite perception),ananta sukha (infinite bliss), and ananta virya (infinite power).
In simple terms, a kevalin is one who knows simultaneously the past, present and future of all the substances along with their modes. It is only a kevalin who is said to be liberated from the shackles of birth, old age, disease, and death.
Kevala jnana (omniscience) is the essential precondition for moksha (emancipation). As knowledge illuminates itself and all other things, a kevalin knows oneself and all others. Thus a kevalin is knowledge-personified knower and the knowable.
Jainism postulates that ananta jnana is latent in all selves. Each self is pure consciousness of knowledge but is obscured by the veil of karmas. Since time immemorial, an infinite number of souls have manifested this inherent potential through right faith, right knowledge, and right conduct, become kevalins and have continued to guide mankind on the moksha marga (pathway of emancipation).
A kevalin may either be a tirthankara kevalin, an omniscient spiritual teacher, or an ordinary kevain embodying kevala jnana (Supreme Knowledge). Jain literature records the biographies of twenty four tirthankara kevalins and many ordinary kevalins who have transcended the worldly sojourn and enjoy unconditional bliss. Along with spiritual heads, teachers, monks, etc. kevalins are regarded as one of the panca parmesthis (five Supreme Ones), yet each is considered unique in Jain tradition.