John 16:4
But I have told you these things so that when their hour comes, you will remember that I told you about them. I did not tell you these things from the beginning, because I was with you.
What it says
Jesus says he tells them now so they will remember his words when the hour comes.
What it is doing
The advance warning is meant to steady their memory.
In context
1“I have told you these things so that you will not fall away. 2They will put you out of the synagogues. In fact, a time is coming when anyone who kills you will think he is offering a service to God. 3They will do these things because they have not known the Father or Me. 4But I have told you these things so that when their hour comes, you will remember that I told you about them. I did not tell you these things from the beginning, because I was with you.