this is a very good and critical (life and death) question. the answer is only known, literally, by those to whom the Father in heaven grants it. (as Yeshua told Peter; and as John the Immerser said plainly) .....
no one who is audibly by a person told it, gets it. no one who trusts man or men, gets it. only those who seek and trust the Father in heaven, through grace by faith in Yeshua, and even that is a Gift, not in any way of ourselves.
there are, btw, many direct statements in Scripture that are understood only by little children, and humble adults who have become as little children, trusting Yahweh as a 3 year old boy trusts completely his earthly father (when he has a good father any way....) ....
simply, the answer is granted by seeking Yahweh Himself, desperately hungry and thirsty FOR HIM, reading all of Scripture through and through.... it takes time usually (some is all at once, once for all.... other takes time, decades, even a life time)........
as it is written. so it is. (for obvious answers to some of your seeking, look at all the different descriptions in the NT about the believers , as you have started to, apparently...) oh, and you can expect to be attacked if you bring up questions at most churches, about Scripture and why they are not like Scripture says.... remember they attacked Yeshua first, and would crucify Him today if they could. some of them actually do 're-crucify' Him daily in their official practice since a little after 300 a.d.)
We read in act, the work of the Holy spirit was clearly visible, from the healing miracle, prophecy, visions etc. And it make the church grow very fast. I wonder, why we hardly see the manifestation of the Holy spirit now. Is that because God do different way now or we as a church not as good as the first church.