Laghu Vakya Vritti is a work attributed to Adi Shankaracharya. It consists of 53 verses and is commented upon by a number of writers both in Sanskrit and in vernacular languages. In this work we have an exhaustive exposition of the great statements of Upanishads, known as Mahavakyas. There are four such statements. One of these is ‘That thou art” (tattvamasi), which has been commented upon by Adi Shankaracharya. This commentary is technically known as vritti. It is a sort of lucid explanation on the original mahavakya, in the form of dialogue between a serious Vedantic student and the spiritual master.
According to Shankaracharya, the absolute consciousness is beyond words and language. Yet words and their arrangement in sentences are helpful in expressing the hidden meaning and mysterious experiences. The words are our guide to reveal the meaning of the entire sentence. Besides the explicit meaning (abhidha), the figurative meaning (lakshana) or implicit meaning (vyanjana) may reveal the real purport of a statement. So the words and the sentence are a composite part of the whole text and indicate the meaning known as lakshyartha of the sacred and holy text. This process of unfolding the sacred content of a sentence is known as vakya vritti. In tattvamasi, tat (that) means Brahman and tvam (you or thou) means jiva (soul) or atma (self). Both are one and the same.
So the vakya-vritti helps us to understand and realize the very consciousness (self) which illuminates thoughts, emotions and the entire working of the body. To meditate on this self is the way to know the ultimate truth and understand the absolute consciousness (Brahman). Such a realized one is liberated soul, free from bondage, and is known as jivanmukta.