Have you not read, ". . . It is written in the prophets, And they shall be all taught of God. Every man therefore that hath heard, and hath learned of the Father, cometh unto me. . . ." -- John 6:45. "And all thy children shall be taught of the LORD; and great shall be the peace of thy children." -- Isaiah 54:13. "And they shall teach no more every man his neighbour, and every man his brother, saying, Know the LORD: for they shall all know me, from the least of them unto the greatest of them, saith the LORD: for I will forgive their iniquity, and I will remember their sin no more." -- Jeremiah 31:34.
Spoken about the children of God, not the children of the devil (world)
The ones who hear are 'of God', John 8, Jesus says those who do not hear are not of the Father. I take that to mean they are not those who are born again. Someone who is born again, is an infant or babe and it is to them the Father reveals the things of God as they are now of God and can listen and hear and respond positively to Christ. The Father reveals the things of God to babes.
Luke 10
21 In that hour Jesus rejoiced in the Spirit and said, “I thank You, Father, Lord of heaven and earth, that You have hidden these things from the wise and prudent and revealed them to babes. Even so, Father, for so it seemed good in Your sight.
22 All things have been delivered to Me by My Father, and no one knows who the Son is except the Father, and who the Father is except the Son, and the one to whom the Son wills to reveal Him.”
You can not believe in Christ if all you are is the old man of the flesh, and have enmity with God. God must change you and He does that by the new birth, otherwise the enmity remains and you will never hear God or believe what Christ says.
Enmity is defined as
en·mi·ty
noun
the state or feeling of being actively opposed or hostile to someone or something.
"decades of enmity between the two countries"
When your born again, (begotten again), you are of God and you live according to the Spirit, you have passed from death into life, you have been made alive spiritually to God and possess eternal life. Then afterwards when you believe, (and all who are born of God will believe in Christ), you are sealed by the Spirit as a guarantee for the future redemption of His purchased possession which is you.
Romans 8
5 For those who live according to the flesh set their minds on the things of the flesh, but those who live according to the Spirit, the things of the Spirit.
6 For to be carnally minded is death, but to be spiritually minded is life and peace.
7 Because the carnal mind is enmity against God; for it is not subject to the law of God, nor indeed can be.
8 So then, those who are in the flesh cannot please God.
9 But you are not in the flesh but in the Spirit, if indeed the Spirit of God dwells in you. Now if anyone does not have the Spirit of Christ, he is not His.
10 And if Christ is in you, the body is dead because of sin, but the Spirit is life because of righteousness.