The NWT renders it “before Abraham came into existence, I have been,” which is grammatically defensible for ego eimi with a past-referring time clause. Don’t Witnesses have a real grammatical case here?

The extension-from-past rendering is defended by some grammarians, and that should be acknowledged. The reply is that the same phrase, ego eimi, is used absolutely in John 8:24 and 8:28 and in Isaiah 43:10 in the Septuagint, forming a pattern of divine self-identification John builds through the chapter; that the crowd’s response was to stone him, which a claim to longevity would not provoke; and that even on the NWT rendering, a being who existed before Abraham and whom the Jews tried to stone for blasphemy is not merely a prophet. The grammar is debated; the context is not.