1 John 1:5
1 John 1:55And this is the message we have heard from Him and announce to you: God is light, and in Him there is no darkness at all.
JWs read "God is light" devotionally and morally — light symbolises truth, righteousness, and Jehovah's pure character against the moral darkness of the world. The verse plays no special role in JW doctrinal disputes; it is simply quoted as a description of God's holiness. The Watchtower's reading does not turn on the verb here because the identity statement does not threaten any Watchtower position.
John writes ho theos phōs estin — "God is light" — using the bare predicative copula. The verse is one of three Johannine identity-statements (with "God is love" at and "God is spirit" at ) where the simple "is" carries the full weight of the claim. Together they form the short list of declarative things the New Testament says God simply IS — not "represents" or "shows" but is. The verse matters apologetically as a control case: the NWT renders "is" as "is" here without difficulty.
The NWT renders the verb "is" — exactly the literal Greek copula — in this verse and at the parallel "God is love" (). Both are doctrinally low-pressure for the Watchtower, and the rendering is unproblematic. The contrast with the Last Supper passages, where the same estin gets swapped to "means," is the point: the rule the NWT applies to the copula scatters with doctrinal pressure, not with grammar.