I'm coming to realize we are on two very different tracks here.
Are you talking about the Gnosticism of NT times?
I'm talking about Gnostic Dualism, such as Paul and John both dealt with. Manichaeism is a Persian religion that exemplifies this dualism, depicting the material world as evil, and a spiritual world as good.
1 Tim 4.1 The Spirit clearly says that in later times some will abandon the faith and follow deceiving spirits and things taught by demons. 2 Such teachings come through hypocritical liars, whose consciences have been seared as with a hot iron. 3 They forbid people to marry and order them to abstain from certain foods, which God created to be received with thanksgiving by those who believe and who know the truth. 4 For everything God created is good, and nothing is to be rejected if it is received with thanksgiving, 5 because it is consecrated by the word of God and prayer.
Col 2.9 For in Christ all the fullness of the Deity lives in bodily form, 10 and in Christ you have been brought to fullness....
16 Therefore do not let anyone judge you by what you eat or drink, or with regard to a religious festival, a New Moon celebration or a Sabbath day. 17 These are a shadow of the things that were to come; the reality, however, is found in Christ. 18 Do not let anyone who delights in false humility and the worship of angels disqualify you. Such a person also goes into great detail about what they have seen; they are puffed up with idle notions by their unspiritual mind. 19 They have lost connection with the head, from whom the whole body, supported and held together by its ligaments and sinews, grows as God causes it to grow.
20 Since you died with Christ to the elemental spiritual forces of this world, why, as though you still belonged to the world, do you submit to its rules: 21 “Do not handle! Do not taste! Do not touch!”? 22 These rules, which have to do with things that are all destined to perish with use, are based on merely human commands and teachings. 23 Such regulations indeed have an appearance of wisdom, with their self-imposed worship, their false humility and their harsh treatment of the body, but they lack any value in restraining sensual indulgence.
1 John 1. That which was from the beginning, which we have heard, which we have seen with our eyes, which we have looked at and our hands have touched—this we proclaim concerning the Word of life. 2 The life appeared; we have seen it and testify to it, and we proclaim to you the eternal life, which was with the Father and has appeared to us. 3 We proclaim to you what we have seen and heard, so that you also may have fellowship with us. And our fellowship is with the Father and with his Son, Jesus Christ. 4 We write this to make our joy complete.
Both Paul and John asserted that Jesus is a very real manifestation of God and His goodness, with the implication that in receiving his Spirit we also can manifest God's authentic goodness, as opposed to poor imitations of Him by men who cover sins over with legalistic works. Christians are called not just to do good deeds, but more, to exhibit a nature that conveys the presence of God. And it is this divine presence that is denied by the pagan world when they reject Christ and attempt to be spiritual by avoiding material realities.
They don't really dispose of their sins--they just ignore them or marginalize them. And their spirituality is a false mix of righteousness and carnality, which conveys a fallen nature not capable of redemption. It is like trying to appear to be a "good person," doing some nice things, while also admitting that is normal for all to indulge in immorality, or simply passing off such moral failings as "normal."
Conveying God's true character is a matter not just of doing good works, but more, showing divine holiness. To do that requires that we adopt a New Nature, which is one of my major points. Unless we adopt a new nature, and choose to make spiritual decisions to live by it, the world will not recognize a change in our character, and will not come to "see God."