Prologue to the Gospel of John

John 1:1 is the first verse in the opening chapter of the Gospel of John. In the Douay–Rheims, King James, New International, and other versions of the Bible, the verse reads:

In the beginning was the Word, and the Word was with God, and the Word was God.

The phrase "the Word" (a translation of the Greek word "Logos") is widely interpreted as referring to Jesus, as indicated in other verses later in the same chapter. This verse and others throughout Johannine literature connect the Christian understanding of Jesus to the philosophical idea of the Logos and the Hebrew Wisdom literature. They also set the stage for later understanding development of Trinitarian theology early in the post-biblical era.

According to Matthew Henry (1662–1714) in his commentary, Jesus is called the "Word" in this opening verse because he was the Son of God sent to earth to reveal his Father's mind to the world. He asserts that a plain reading of the verse written by John the Evangelist should be understood as proof that Jesus is God; that Jesus has the same essence as God and existed with God the Father from the very beginning, the Word was with God, and the Word was God.

Tertullian in the early third century wrote:

Now if this one [the Word] is God according to John ("the Word was God"), then you have two: one who speaks that it may be, and another who carries it out. However, how you should accept this as "another" I have explained: as concerning person, not substance, and as distinction, not division.

And a little later:

And that you may think more fully on this, accept also that in the Psalm two gods are mentioned: "Thy throne, God, is forever, a rod of right direction is the rod of thy kingdom; thou hast loved justice and hated iniquity, therefore God, thy God, hath anointed thee." If he is speaking to a god, and the god is anointed by a god, then also here he affirms two gods... More is what you will find just the same in the Gospel: "In the beginning was the Word, and the Word was with God, and the Word was God": One who was, and another in whose presence he was.

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