That's not what He said. In v.18 He was referring to His Second Advent. In v.19 He was affirming the disciples that they had eternal life and would see Him again. This doesn't refer to the Second Advent, but the fact that they will be in heaven when they die, because He will already be there.
If you take v.18 to be a reference to the Holy Spirit, then there is no difference between Jesus and the Spirit. But there is. They are two separate but equal Personalities.
If you take v.18 to be a reference to the Holy Spirit, then there is no difference between Jesus and the Spirit. But there is. They are two separate but equal Personalities.
John 16: 16 “A little while, and you will no longer see me, and again a little while, and you will see me.” 17 Then some of his disciples said to one another, “What does he mean by saying to us, ‘A little while, and you will no longer see me, and again a little while, and you will see me’; and ‘Because I am going to the Father’?” 18 They said, “What does he mean by this ‘a little while’? We do not know what he is talking about.” 19 Jesus knew that they wanted to ask him, so he said to them, “Are you discussing among yourselves what I meant when I said, ‘A little while, and you will no longer see me, and again a little while, and you will see me’? 20 Very truly, I tell you, you will weep and mourn, but the world will rejoice; you will have pain, but your pain will turn into joy. 21 When a woman is in labor, she has pain, because her hour has come. But when her child is born, she no longer remembers the anguish because of the joy of having brought a human being into the world. 22 So you have pain now; but I will see you again, and your hearts will rejoice, and no one will take your joy from you. 23 On that day you will ask nothing of me.[c] Very truly, I tell you, if you ask anything of the Father in my name, he will give it to you.[d] 24 Until now you have not asked for anything in my name. Ask and you will receive, so that your joy may be complete.
if you read through John 14-17 it is obvious that Jesus is talking about Pentecostal coming of the Holy Spirit.
But if you prefer, look at 'a little while'.
Somewhere in the forty days after Jesus was resurrected he says, 'in a little while you won't see me'.
So 'a little while' here is a matter of a few days. e.g. 10 , 20 whatever.
Then he tells the disciples that they will see him 'a little while' later after he's gone.
So it is crystal clear that 'a little while' is a matter of a few days, (10 days in fact),
and not thousands of years.