Passage
Believest thou not that I [am] in the Father, and that the Father is in me? The words which I speak to you I do not speak from myself; but the Father who abides in me, he does the works.
Believest thou not that I [am] in the Father, and that the Father is in me? The words which I speak to you I do not speak from myself; but the Father who abides in me, he does the works.
John 14:8 Philip says to him, Lord, shew us the Father and it suffices us.
John 14:9 Jesus says to him, Am I so long a time with you, and thou hast not known me, Philip? He that has seen me has seen the Father; and how sayest thou, Shew us the Father?
John 14:10 Believest thou not that I [am] in the Father, and that the Father is in me? The words which I speak to you I do not speak from myself; but the Father who abides in me, he does the works.
John 14:11 Believe *me* that I [am] in the Father and the Father in me; but if not, believe me for the works' sake themselves.
John 14:12 Verily, verily, I say to you, He that believes on me, the works which I do shall he do also, and he shall do greater than these, because I go to the Father.
The verse centers on "believest", "thou", "father", "words", "speak", and "myself". It is saying that the verse draws attention to "believest" and "thou", so its meaning should be read from those terms before moving to application.
The nearby context moves from verse 9's "Jesus says to him Am I so..." into verse 11's "Believe me that I am in the...", so "believest" and "thou" 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 "believest" and "thou" with trust shaped by these words, not by a vague optimism outside the passage.