The phrase is found in verse 6 of chapter 14 of the Gospel of John, as part of Jesus' Farewell Discourse during the Last Supper: "5 Thomas said to him, 'Lord, we do not know where you are going.
[1][2] In the Latin Vulgate, verse 6 states: "dicit ei Iesus ego sum via et veritas et vita nemo venit ad Patrem nisi per me".
This concept is foundational to Christian theology and the primary mechanism by which the metaphysics of Christianity establish a separation between theological principles of the earlier Judaism and other Abrahamic religions, in addition to Pauline directives not to practice the mitzvot and an establishment of Jesus Christ as divine.
It only appears in John 14:6, likely the latest of the gospels, and consistent with the debates about the divinity of the Christian messiah and the split that was occurring in the earliest churches between orthodoxy and Arianism.
The more liberal interpretations see this verse as an exultation and not a mandatory commandment, believing that any human being will receive eternal reward provided they live an ethical life and treat others according to the principles of the golden rule.