Jesus did not hide His identity.  He was a King, although He was careful to say that His kingdom did not have any land territory (John 18:36).  All kings and rulers have to be appointed and recognised by their people, but Jesus was appointed and anointed by God (Psalm 2:6).

He is the King of the kingdom of God; and He will always be the King.  The job of a king is to rule, not just to claim territory, but to direct the way people live.  So, because Jesus is King, He has the right to tell people how to live and who to worship.  Jesus 'testified to the truth' - He said what is true, He lived it, He explained it and He taught His trainee apostles; and He always tells the truth because He is the Truth (John 14:6).
 
Although Pilate was the highest authority in Roman occupied Israel, Jesus was higher than him.  Pilate thought that Jesus should listen to him, but he was wrong.  If Pilate had been interested in the truth, he would have done less talking and much more listening.
 
It is still true that those who want to know the truth will listen to Jesus.  People who refuse to welcome Jesus cannot know the truth which will set them free (John 8:32).  But those who are hungry for righteousness will find it in Jesus.  Deciding to listen to Jesus separates those who are on the side of truth from those who reject His authority and believe lies.  The best way to know what Jesus is saying is by reading the Bible and allowing Him to speak into your heart.  It is a great test of the willingness of our friends and colleagues to be open to the truth.  If they refuse to hear or read God’s Word they are rejecting Christ’s authority, but if they welcome His Word they are showing a hunger for truth which He will satisfy.