John 1:4
John 1:44In Him was life, and that life was the light of men.
JWs generally pass over this verse quickly, because in the NWT it no longer says what it says in other Bibles. Where the rendering is discussed, the life in view is treated as life Jesus received and then passed on as Jehovah's agent — consistent with the Watchtower reading of ("I live because of the Father") as proof that Jesus owes his existence to someone else. Life is something granted to him, not something he has in himself.
Four words carry the weight: "In him was life." Not life given, not life relayed — life resident. John says the same thing again in , where the Father has granted the Son "to have life in himself." That last phrase is the point. Creatures have life derivatively; they hold it the way a room holds borrowed light. To have life in yourself is what distinguishes the Creator from everything he made. This is also the verse to reach for when a JW presses — "I live because of the Father." Read the whole of that sentence with them: "so also the one who feeds on me will live because of me." If the first half proves Jesus owes his origin to the Father, the second half proves believers owe their origin to Jesus, by identical grammar. Neither half is about origin. Both are about the life that flows from the sender to the sent. tells you where that life started.
The NWT moves the clause boundary. Standard translations end verse 3 at "that has been made" and begin verse 4 with "In him was life." The NWT reads instead: "What has come into existence by means of him was life, and the life was the light of men." The effect is that the verse stops saying life was in him and starts saying life was one of the things that came into existence through him — a created product rather than something he possesses. The Greek phrase in question (ho gegonen) can be attached either way and the earliest manuscripts carry no punctuation, so this is a translator's choice rather than a settled reading. It is worth noticing which choice was made, and that it moves the verse away from , where the Son has life in himself.