Passage
and ye also do testify, because from the beginning ye are with me.
and ye also do testify, because from the beginning ye are with me.
John 15:25 but--that the word may be fulfilled that was written in their law--They hated me without a cause.
John 15:26 `And when the Comforter may come, whom I will send to you from the Father--the Spirit of truth, who from the Father doth come forth, he will testify of me;
John 15:27 and ye also do testify, because from the beginning ye are with me.
The verse centers on "testify" and "beginning". It is saying that the verse draws attention to "testify" and "beginning", so its meaning should be read from those terms before moving to application.
The prior verse says "And when the Comforter may come whom...", giving immediate footing for "testify" and "beginning". 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 "testify" and "beginning" with trust shaped by these words, not by a vague optimism outside the passage.