Related Holy Ghost revealing truth privately and personally in an absolute and unmistakable manner
In recent posts I have seen many statements that seem to indicate spiritual experience as secondary/lesser/untrusted sources of truth:
Truth must be determined by something not so much apart from a personal subjective experience but in addition to it. That brings us to the realm of empirical evidence and rational thought.1
the Bible warns against emotional 'feelings' and 'spiritual experiences' that are not utterly rooted in following the Jesus of the Bible ... I am a sceptic when it comes to people enthusing about an experience they had after prayer...Especially if it ... does not square with what my Bible tells me Jesus Christ is.2
any personal private revelation which contradicts something that has already been written or does not deepen understanding of who Jesus is and what Jesus does (according to what is already written) is to be held as highly suspect at best.3
However, they may acknowledge varying degrees of clarity in these revelations, and the possibility of deception (as in false dreams, false visions, or false prophecies), which is why discernment of spirits is an important subject matter.4
From Wikipedia of discerning spirits5:
Judgment of discernment can be made in two ways. The first is by a charism or spiritual gift, held as divinely granted to certain individuals for the discerning of spirits by intuition (1 Corinthians 12:10). The second way to discern spirits is by reflection and theological study. This second method is by acquired human knowledge
While my own opinions are closer to the fourth statement, what is the biblical basis that spiritual experiences are the first step in conversion (are to be trusted)? Is anything else necessary in knowing Jesus is the Christ (Savior of man), is theological study necessary? Is anything else more important to conversion/following Jesus than feelings/heart/faith (is data, reasoning, evidence, etc)?
Bonus: How does one discern that which is good/evil (deceiving spirits and false prophets vs truth)?
I do realize these statements include caveats such as ...are not utterly rooted in following the Jesus of the Bible
and ...which contradicts something that has already been written or does not deepen understanding of who Jesus..(according to what is already written)
but both of these emphasize relying on one's understanding of the written word of which there are many interpretations. We know the bible doesn't contain everything (Jesus' teenage years, John 20:30 to quickly name a few as this is laying quick basis). As many parts of the bible were written after they happened things could have been missed or changed in the mind (not nefariously/purpose). This isn't to say the bible isn't important or doesn't contain truth (I am asking for biblical basis to answer this question), just that relying on it as singular/primary source has inherent flaws
1 https://christianity.stackexchange.com/a/100625/22319
2 https://christianity.stackexchange.com/a/100617/22319
3 https://christianity.stackexchange.com/a/100652/22319
4 https://christianity.stackexchange.com/a/100647/22319
5 Gen 3:22, 1 king 3:9, Isa 5:20, Eze 44:23, John 1:9, 1 Cor 2:14, 1 Cor 12:10, 1 John 4:2,6