The kingdom doesn’t come with observation. Could you reconcile your understanding with this statement that Jesus made?
I'm not exactly certain of what you want me to reconcile, but for your consideration, I believe Christ said this because the Jews were expecting the promised Messiah to establish the PHYSICAL Kingdom of God on this earth during this age of time. For this reason, Christ says the Kingdom of God NOW in this age that He ushered in is not a physical Kingdom they expected because the Kingdom of God in this age of time is spiritual and is within you.
Since the Kingdom of God that came when Christ came to earth a man, evidenced when He cast out devils cannot be within you and be a physical Kingdom.
Matthew 12:28 (KJV) But if I cast out devils by the Spirit of God, then the kingdom of God is come unto you. (also Lu 11:20)
Luke 17:20-21 (KJV) And when he was demanded of the Pharisees, when the kingdom of God should come, he answered them and said, The kingdom of God cometh not with observation: Neither shall they say, Lo here! or, lo there! for, behold, the kingdom of God is within you.
John 18:33 (KJV) Then
Pilate entered into the judgment hall again, and called Jesus, and said unto him, Art thou the King of the Jews?
John 18:36-39 (KJV) Jesus answered,
My kingdom is not of this world: if my kingdom were of this world, then would my servants fight, that I should not be delivered to the Jews:
but now is my kingdom not from hence. Pilate therefore said unto him,
Art thou a king then? Jesus answered, Thou sayest that I am a king. To this end was I born, and for this cause came I into the world, that I should bear witness unto the truth. Every one that is of the truth heareth my voice. Pilate saith unto him, What is truth? And when he had said this,
he went out again unto the Jews, and saith unto them, I find in him no fault at all. But ye have a custom, that I should release unto you one at the passover: will ye therefore that I release unto you the King of the Jews?
When Christ explains to Nicodemus how man who is fully grown must be born again. But not through being physically born again, but born again of the Spirit within him. Once again proving that the Kingdom of God is not a physical Kingdom that would be of this world, but is the SPIRITUAL Kingdom of God in heaven, that man can both know (see) and enter when they have been born again of the Spirit of Christ.
John 3:3-7 (KJV) Jesus answered and said unto him, Verily, verily, I say unto thee,
Except a man be born again, he cannot see the kingdom of God. Nicodemus saith unto him, How can a man be born when he is old? can he enter the second time into his mother's womb, and be born? Jesus answered,
Verily, verily, I say unto thee, Except a man be born of water and of the Spirit, he cannot enter into the kingdom of God. That which is born of the flesh is flesh; and that which is born of the Spirit is spirit. Marvel not that I said unto thee, Ye must be born again.
John 4:23-24 (KJV) But the hour cometh, and now is, when the true worshippers shall worship the Father in spirit and in truth: for the Father seeketh such to worship him.
God is a Spirit: and they that worship him must worship him in spirit and in truth.
I hope this is what you were looking for.