There is no such thing as "believing in your spirit".
We believe in our spirit, through the testifying with our spirit.
Born Again “ of the Spirit “ ....our spirit is Born Again only by the Living seed of God.....His Living Spirit , who indwells our spirit, starts his work in us the moment we become his spiritual child, making us into the image of Jesus......Gods Spirit is very much Alive and Active in his children’s spirit, for as his word says, I will give you a new heart and spirit within.
Where does he put this new heart within us, if not our spirit, when our spirit becomes “ Born Of The Spirit “?
The new Spirit that he puts in us is that of Jesus Spirit, our spirit will be consumed by the Spirit of God, we will be made into Jesus image, because we are spiritual Sons and Daughters.
A New Heart and Spirit
…25I will also sprinkle clean water on you, and you will be clean. I will cleanse you from all your impurities and all your idols. 26
I will give you a new heart and put a new spiritwithin you; I will remove your heart of stoneand give you a heart of flesh. 27And I will put My Spirit within you and cause you to walk in My statutes and to carefully observe My ordinances.
We are led by the Spirit, that’s why we must be Born Of The Spirit...to be led by the Holy Spirit, there is no leading without being Born Of The Spirit, our spirit is led....
Heirs with Christ
…13For if you live according to the flesh, you will die; but if by the Spirit you put to death the deeds of the body, you will live. 14
For all who are led by the Spirit of God are sons of God. 15For you did not receive a spirit of slavery that returns you to fear, but you received the Spirit of sonship, by whom we cry, “Abba! Father!”…
That is why we must be Born Again of imperishable seed that liveth and abideth forever.
How else would I have known I was Born Of The Spirit if the Holy Spirit hadn’t testified with my spirit ( spoke to my spirit as he was indwelling my spirit, that I was his child, The Holy Spirit speaks to his Born Again children, .....that’s how we communicate with God via our spirit ?)......Biblical.
Romans 8
King James Version
8 There is therefore now no condemnation to them which are in Christ Jesus, who walk not after the flesh, but after the Spirit.
2 For the law of the Spirit of life in Christ Jesus hath made me free from the law of sin and death.
3 For what the law could not do, in that it was weak through the flesh, God sending his own Son in the likeness of sinful flesh, and for sin, condemned sin in the flesh:
4 That the righteousness of the law might be fulfilled in us, who walk not after the flesh, but after the Spirit.
5 For they that are after the flesh do mind the things of the flesh; but they that are after 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, neither indeed can be.
8 So then they that are in the flesh cannot please God.
9 But ye are not in the flesh, but in the Spirit, if so be that the Spirit of God dwell in you. Now if any man have not the Spirit of Christ, he is none of his.
10 And if Christ be in you, the body is dead because of sin; but the Spirit is life because of righteousness.
11 But if the Spirit of him that raised up Jesus from the dead dwell in you, he that raised up Christ from the dead shall also quicken your mortal bodies by his Spirit that dwelleth in you.
12 Therefore, brethren, we are debtors, not to the flesh, to live after the flesh.
13 For if ye live after the flesh, ye shall die: but if ye through the Spirit do mortify the deeds of the body, ye shall live.
14 For as many as are led by the Spirit of God, they are the sons of God.
15 For ye have not received the spirit of bondage again to fear; but ye have received the Spirit of adoption, whereby we cry, Abba, Father.
16 The Spirit itself beareth witness with our spirit, that we are the children of God:
17 And if children, then heirs; heirs of God, and joint-heirs with Christ; if so be that we suffer with him, that we may be also glorified together.