What is Eschatology? Why is it important for us to know?
Gnosticism comes from the ancient Greek word “gnostikos” and means “having knowledge,” so Gnosticism is based upon knowledge and has little regard for the physical world. Gnostics teach that material or physical matter is evil because the world was created imperfectly. To them, God is unknowable, and this unknowable God gave rise to many lesser spirit beings called Aeons, so they actually believe that a lower spirit being created the universe and not God, the One, true Creator. Astonishingly, Gnostics don’t even deal with sin because they believe salvation is achieved by getting in touch with the secret knowledge that most do not know about. This creates a prideful heart since they feel superior compared to others who are less knowledgeable about God, but the fact is, they don’t know the real God. This may be one reason Jude “found it necessary to write appealing to you to contend for the faith that was once for all delivered to the saints” (Jude 1:3), because even in the church’s infancy, the church was already having to contend for the original gospel (1 Cor 15:3-6). Paul told Timothy he must “Fight the good fight of the faith” (1st Tim 6:12), because so many were preaching another gospel and not the one Jesus delivered of repentance and faith (Mark 1:14-15).
It wasn’t long before the Gnostics had already infiltrated the church. They felt it was only through knowledge that one could be saved, and that meant it was only for a select few, however the Bible teaches that whomever will come to Christ can be saved (John 6:35-37). Knowledge about how to be saved is not enough. Many know how to be saved but still reject Christ, and by rejecting Christ, they close the door on the only way they can be saved (John 6:44). Eternal life only comes as a free gift from God (Eph 2:8-9). It cannot be earned by knowledge. Today it appears that Gnosticism is alive and well in some circles, teaching that we must search the Scriptures for meaning and for the way of salvation, but the gospel is not hidden like a treasure and you have to figure out where it is. It is plainly revealed in Scripture; so clearly that even a young child can be saved. Gnosticism, coming from the Greek word “gnosis,” meaning “knowledge,” wrongly believes that salvation can only be obtained through special knowledge and that most of this knowledge is not plainly revealed in the Bible. We know this isn’t true, and besides, that looks a lot like a works-oriented salvation, where it depends on the person to be saved. The Bible teaches that dead people can’t resurrect themselves to new life in Christ any more than Lazarus could! They need the Spirit’s quickening (Eph 2:1-4). If we must figure all this out, then that makes us responsible for our own salvation, and of course, that is not what the Bible teaches. In fact, nothing could be further from the truth (Eph 2:8-9). There are no works we can do in regards to becoming a child of God. We can’t be saved by works, by “finding secret Bible codes,” or by discovering some “hidden knowledge” that most people can’t find. That’s a type of works, and God will not accept our works.
Sadly, Gnostics don’t understand that we “are not in the flesh but in the Spirit, if in fact the Spirit of God dwells in you. Anyone who does not have the Spirit of Christ does not belong to him” (Rom 8:9). Spiritual knowledge, like why we need the Savior, is not gained by empirical knowledge because “The natural person does not accept the things of the Spirit of God, for they are folly to him, and he is not able to understand them because they are spiritually discerned” (1 Cor 2:14). Jesus said “the Spirit of truth, whom the world cannot receive, because it neither sees him nor knows him. You know him, for he dwells with you and will be in you” (John 14:17), so without the Spirit of God, we cannot understand the things of God, so knowledge alone is insufficient to save us. I would like to ask the Gnostics, just “who has understood the mind of the Lord so as to instruct him” (1 Cor 2:16)? Not you and not me.
You could graduate from Harvard or Yale with the highest degree possible, and still not understand the things of God without the Spirit of God. Knowledge is not enough. It’s enough to build an aircraft, but it’s not enough to know how to receive eternal life. Knowledge can help you know about the heavens, but not how to get there. Knowledge is temporal, but the spiritual is eternal. Having knowledge alone only does one thing, it “puffs up” (1 Cor 8:1), or it fills a person with pride, and God will always resist the proud (James 4:6). Like many, the Gnostics, by “Claiming to be wise, they became fools” (Rom 1:22). The root word, Gnosis, refers to knowledge, but it’s based upon personal experience or perception; on the other hand, salvation is fully a work of God and God’s Spirit reveals Who He is, Who Christ is, and why we Jesus. Knowledge alone can only tell us “how to,” but the Spirit of God can reveal the Word of God and create the children of God. Human knowledge cannot ever do that. In fact, it’s contrary to God’s ways. The wisdom of man is foolishness to God (1 Cor 1:12, 3:19).
Gnostics claim that they were part of the original church, but church historians have declared them heretics. Today, there is no shortage of cults and false churches that still teach that knowledge is the way to God when Jesus is the one and only way to the Father (John 6:44; Acts 4:12). There is no way to attain eternal life simply by studying and gaining knowledge. The only knowledge we need is to acknowledge that we’re sinners in need of a Savior, and that Jesus Christ is the only way we can be saved (Acts 16:30-31). To believe as the Gnostics do, that knowledge is the way to God, is to bypass Jesus Christ. He is the one and only way. That’s the only knowledge we need to be saved. All other human knowledge is worthless compared to knowing God and Jesus Christ, the Son of God. The Apostle Paul asked, “How then will they call on him in whom they have not believed? And how are they to believe in him of whom they have never heard? And how are they to hear without someone preaching” (Rom 10:14)? It doesn’t take studying knowledge to find God. It takes a person of God, sharing the Word of God, having the Spirit of God, to make the children of God, for the glory of God. And nothing else matters but His glory (Psalm 115:1).
Here is some related reading for you: What do Agnostics Believe: What do they Say about Jesus? 
Resource – Scripture quotations are from The Holy Bible, English Standard Version® (ESV®), Crossway Bibles. (2007). ESV: Study Bible : English standard version. Wheaton, Ill: Crossway Bibles. Used by permission. All rights reserved.