God changes us instantly when HE reveals HIMSELF to us. We are indeed "a new creature". Old things are passed away. Things are not the same as they were before.
II Corinthians 5
17 Therefore if any man be in Christ, he is a new creature: old things are passed away; behold, all things are become new.
18 And all things are of God, who hath reconciled us to Himself by Jesus Christ, and hath given to us the ministry of reconciliation;
19 To wit, that God was in Christ (The Word), reconciling the world unto Himself, not imputing their trespasses unto them; and hath committed unto us the word of reconciliation.
We are born again because God chooses to reveal HIMSELF to us and to reveal Jesus, The Word, to us. It is not because we do anything to earn being born again. It is just God's will that we are born again and that we are HIS creation.
Romans 9
15 For HE saith to Moses, I will have mercy on whom I will have mercy, and I will have compassion on whom I will have compassion.
16 So then it is not of him that willeth, nor of him that runneth, but of God that sheweth mercy.
17 For the scripture saith unto Pharaoh, Even for this same purpose have I raised thee up, that I might shew my power in thee, and that MY name (The Word) might be declared throughout all the earth.
18 Therefore hath HE mercy on whom HE will have mercy, and whom HE will HE hardeneth.
19 Thou wilt say then unto me, Why doth HE yet find fault? For who hath resisted HIS will?
20 Nay but, O man, who art thou that repliest against God? Shall the thing formed say to him that formed it, Why hast thou made me thus?
21 Hath not the potter power over the clay, of the same lump to make one vessel unto honour, and another unto dishonour?
22 What if God, willing to shew His wrath, and to make His power known, endured with much longsuffering the vessels of wrath fitted to destruction:
23 And that HE might make known the riches of HIS glory on the vessels of mercy, which HE had afore prepared unto glory,
24 Even us, whom HE hath called, not of the Jews only, but also of the Gentiles?
25 As he saith also in Osee, I will call them my people, which were not my people; and her beloved, which was not beloved.
26 And it shall come to pass, that in the place where it was said unto them, Ye are not my people; there shall they be called the children of the living God.
27 Esaias also crieth concerning Israel, Though the number of the children of Israel be as the sand of the sea, a remnant shall be saved:
29 And as Esaias said before, Except the Lord of Sabaoth had left us a seed, we had been as Sodoma, and been made like unto Gomorrha.
30 What shall we say then? That the Gentiles, which followed not after righteousness, have attained to righteousness, even the righteousness which is of faith.
31 But Israel, which followed after the law of righteousness, hath not attained to the law of righteousness.
32 Wherefore? Because they sought it not by faith, but as it were by the works of the law. For they stumbled at that stumblingstone;
33 As it is written, Behold, I lay in Sion a stumblingstone and rock of offence: and whosoever believeth on him shall not be ashamed.
Most church goers today are not born again. They reject the subject of an elect of God. They work to earn their position in the body of Christ. Some in ministry even work to rise from one ministry office to another, not realizing these offices are appointed by Jesus and are not earned by works of man. (Ephesians 4:8;11-12)
These people who attend churches and call themselves Christians put themselves into the church by joining the church or being baptized in the church without being born of the Spirit of God and they resist all mention of the Holy Spirit who is the great gift given by God to the New Testament church.
The Holy Spirit lives in each believer and does the following works for that believer:
John 14:26 But the Comforter, which is the Holy Ghost, whom the Father will send in my name, he shall teach you all things, and bring all things to your remembrance, whatsoever I have said unto you.
John 16:13 Howbeit when he, the Spirit of truth, is come, he will guide you into all truth: for he shall not speak of himself; but whatsoever he shall hear, that shall he speak: and he will shew you things to come.
14 Which is the earnest of our inheritance until the redemption of the purchased possession, unto the praise of His glory.
I Corinthians 3:16 Know ye not that ye are the temple of God, and that the Spirit of God dwelleth in you?
I Corinthians 6:19-20 What? know ye not that your body is the temple of the Holy Ghost which is in you, which ye have of God, and ye are not your own? For ye are bought with a price: therefore glorify God in your body, and in your spirit, which are God's.
32 And before Him shall be gathered all nations: and HE shall separate them one from another, as a shepherd divideth his sheep from the goats:
33 And HE shall set the sheep on His right hand, but the goats on the left.
34 Then shall the King say unto them on his right hand, Come, ye blessed of my Father, inherit the kingdom prepared for you from the foundation of the world: