Krisna Pillai developed and modernized Christian religious texts and other such works in Tamil literature. The style of composition, formation of the Tamil language, imagination and usage in his compositions illustrate the profound study of the Kambaramayanam by the Tamil Christian poet and scholar. One of the most prominent works of the poet Krisna Pillai is the epic entitled Iratcaniya Yattirikam, which fetched him enormous fame and popularity. The work comprises of three thousand and eight hundred poems and hymns. This poetic work of Tamil literature is much admired for its manner of composition and writing and its articulacy, elegance, smooth flowing style and simple presentation. Although the work consists of twenty one poems that depict that the Tamil Christian poet was skilled and an expert in composing matakku, ciletai, tiripu and yamakam verses as well.
During that era, such poems with a play on words were considered as an indication of brilliance and merit amongst authors and poets in the Tamil country. Krisna Pillai's magnum opus, the Tamil epic of Iratcaniya Yattirikam was adapted from the popular literary work titled The Pilgrim's Progress, written by another Christian author John Bunyan. The work was composed by Krisna Pillai for the Tamil people and was constructed in the literary conventions found in Tamil literature.
Similar to the hymns and verses composed by the much revered Tamil Nayanmars and Tamil Alvars, the devotional poems in this Tamil epic work fascinates and enthralls the minds of the readers. The Tamil version of the original English work composed by the Tamil Christian poet Krisna Pillai describes various tales related to the human soul, its encounter with grief and sadness and ultimately the attainment of the grace of Lord Jesus Christ and the final progression of life to heaven. The protagonist of the epic is a Christian. The work is still popular among modern Tamil Christians.