Joh 3:11 Most assuredly, I say to you, We we speak what we know and testify what we have seen, and you do not receive Our witness.
Jesus made it clear to the Samaritan woman in Joh 4 that they worshiped what they didn’t know. A chapter earlier He is confronting Nicodemus with the same, vs. “11 Most assuredly, I say to you, We speak what We know and testify what we have seen,…” Similar experience with Philip, God led him to meet an Ethiopian Eunuch, Acts 8:30 “So Philip ran to him, and heard him reading the prophet Isaiah, and said, “Do you understand what you are reading?”
Salvation is by revelation that comes about when God takes His spoken Word and makes it alive in a person He is saving to understand (convince) that they are sinners in need of a Savior, and what He has done for them in Christ on the cross. With that knowledge they respond in repentance and faith, “…faith comes by hearing, and hearing by the word of God” (Rom 10:17). This does not happen apart from the preaching of the law and the gospel as Jesus and others did. We must get to know Him before we can love Him, and then love Him before we can desire to obey Him.