John chapter 18, verse 38 of the Gospel of John, is often referred to as "jesting Pilate" or "What is truth?", of Latin Quid est veritas?. In it, Pontius Pilate questions Jesus' claim that he is "witness to the truth" ().
Following this statement, Pilate proclaims to the masses (lit., "the Jews" referring to the Jewish authorities) that he does not consider Jesus guilty of any crime.
The exact intention of Pilate has been subject to debate among scholars, with no firm conclusion. His statement may have been made in jest that the trial was a mockery, or he may have actually intended to reflect on the philosophical position that truth is hard to ascertain. The Greek word rendered as "truth" in English translations is "aletheia", which literally means "unconcealed" and connotes sincerity in addition to factuality and reality.
This verse reflects the Christian tradition of the "guiltlessness of Jesus" in Pilate's Court. The innocence of Jesus is important in the Gospel of John, given that it emphasizes Jesus as the Lamb of God.
Note that Jesus, although he does not respond to Pilate's question (perhaps because Pilate "went out again" before giving him a chance to) believes he knows the answer. During his prayer in Gethsemane, Jesus tells God, "Sanctify them through thy truth: thy word is truth." (John 17:17)
In addition to the guiltlessness of Jesus this verse also reflects the rejection of the truth of God: Jesus, the witness to truth was rejected, ignored and condemned.
This verse has been widely quoted and alluded to in culture and literature, particularly in that of philosophical nature. While Pilate's question -- whether intended philosophically, jestfully, rhetorically, or born of frustration at the lack of a plain answer -- is by no means the only incident of someone questioning the nature of truth, it has been drawn upon many times as a significant occurrence thereof.
Francis Bacon uses this musing to open his essay Of Truth, saying that Pilate "would not stay for an answer". He uses this to introduce his theme of truth as an affirmation of faith.