Passage
The Jews therefore said to him: Thou art not yet fifty years old. And hast thou seen Abraham?
The Jews therefore said to him: Thou art not yet fifty years old. And hast thou seen Abraham?
John 8:55 And you have not known him: but I know him. And if I shall say that I know him not, I shall be like to you, a liar. But I do know him and do keep his word.
John 8:56 Abraham your father rejoiced that he might see my day: he saw it and was glad.
John 8:57 The Jews therefore said to him: Thou art not yet fifty years old. And hast thou seen Abraham?
John 8:58 Jesus said to them: Amen, amen, I say to you, before Abraham was made, I AM.
John 8:59 They took up stones therefore to cast at him. But Jesus hid himself and went out of the temple.
The verse centers on "jews", "therefore", "said", "thou", "fifty", "years", and "hast". It is saying that the verse draws attention to "jews" and "therefore", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 56's "Abraham your father rejoiced that he might..." into verse 58's "Jesus said to them Amen amen I...", so "jews" and "therefore" belong inside that flow. In John context, the local focus is the identity of Jesus, new birth, eternal life, and belief and unbelief.
A plain takeaway is to answer the verse's own emphasis on "jews" and "therefore" with trust shaped by these words, not by a vague optimism outside the passage.