How do we know the words accredited to Jesus were the words Jesus actually spoke? were people making notes of what Jesus said at the time or are the accounts in the N/T just people trying to remember what they were told he said?
We do not have the verbatim words of Jesus because Jesus mostly spoke Aramaic and the New Testament was written in Greek.

It is not important whether what we have is verbatim or not. What is more important is what the message tries to convey. A single idea can be conveyed in many languages without losing its original message. 

We can also be rest assured that we have the right message passed down to us through the ages because the scripture was written with the inspiration of the Holy Spirit and God is faithful in protecting his Message from coruption.


  For prophecy never had its origin in the human will, but prophets,
  though human, spoke from God as they were carried along by the Holy
  Spirit. (2 Peter 1:21, NIV)