“I have much to say in judgment of you. But he who sent me is reliable, and what I have heard from him I tell the world.”
McGarvey points out that “Up to this point Jesus had sought to reveal himself; from this point on he would reveal his enemies also, and though the revelation would be displeasing, it was from the Father, and hence would be spoken.” (TFG 456) The reason for this is that Jesus is a faithful witness (Isaiah 55:4, Rev 3:14).
Isaiah 55:4 See, I have made him a witness to the peoples, a leader and commander of the peoples.
Rev 3:14 “To the angel of the church in Laodicea write: These are the words of the Amen, the faithful and true witness, the ruler of God’s creation.
Notice the audience to whom Jesus will reveal the things spoken by the Father: the world. Jesus did not come to save just the Jewish nation, but the whole world.