John 20:31

This verse unites many of the most important themes in the fourth Gospel. John’s purpose was clearly evangelistic. His Gospel is an excellent portion of Scripture to give to an unbeliever. It is probably the most effective evangelistic tool available. Its impact on the reader is strongest when one reads it through at one sitting, which takes most people less than two hours. This document can also deepen and establish the faith of any believer, and John undoubtedly wrote what he did to accomplish that end as well.

The implication of this primary evangelistic purpose is that John meant unbelievers when he wrote "you." Did he have a particular group of unbelievers in mind, or was he addressing any unbelieving reader? Some commentators have tried to identify a particular audience from statements in the text. Yet it seems more probable that John wrote for a general audience since he did not identify his intended audience specifically. His presentation of Jesus as the divine Son of God certainly has universal application.

"There cannot be any doubt but that John conceived of Jesus as the very incarnation of God." [Note: Morris, p. 756.]

John’s purpose was not academic; it was not simply that people might believe intellectually that Jesus is the divine Messiah. It was rather that they might believe those foundational truths so they could possess and experience the life of God fully (cf. John 10:10). This divine life affects the whole person, not just the intellect. Moreover it affects him or her forever, not just during that person’s present lifetime.

John’s clear purpose statement concludes the body of this Gospel. I regard John 20:31 as the key verse in John’s Gospel.