What are some biblical passages against Gnosticism?

In particular I'm looking for passages that reject the notion that "the material universe is considered evil".
I guess the possible answer to the Genesis passage is that there are some things that are not created by God and those things are thus evil. Anything to refute that argument.

Nothin sorry...

The first argument I could make would be in Genesis. Throughout the creation story, God looks at what he created, the material world, and said it was good. That is one of the reasons why Gnostics believe that the God of the Old Testament is not the almighty God, he is a lesser God.

In response to your revised question which states that there are things God did not create. Consider John 1:3-4:

All things came into being through him, and without him not one thing came into being. What has come into being in him was life, and the life was the light of all people.

Colossians 1:14 - In who me we have redemption through His blood, even the forgiveness of sins:

vs.15 - Who is the image of the invisible God, the first-born of every creature:

vs.16 - For by Him were all things created, that are in heaven, and that are in earth, visible, and invisible, whether they be thrones, or dominions, or rulers, or authorities: all things were created by Him and for Him:

vs.17 - And He is before all things, and by Him all things exist.

Genesis 1:1 In the beginning God created the heavens and the Earth.

Vs.10,12,21,25 - .....And God saw that it was good

I agree with Demon Deacon..

PHYSICAL CREATION is GOOD
Genesis 1 -God saw that everything he created was GOOD.

But there are three other major proofs that the material world is NOTintrinsically evil, viz.,

1) THE INCARNATION

Joh 1:14 And the Word became FLESH and dwelt among us, and we have seen his glory, glory as of the only Son from the Father, full of grace and truth.
1Jo 1:1 That which was from the beginning, which we have heard, which we have seen with our eyes, which we looked upon and have touched with our hands, concerning the word of life

Col 2:9 For in him the whole fullness of deity dwells bodily

This last verse connects also to the SECOND proof
2) PHYSICAL RESURRECTION of Jesus


1Co 15:3-5 For I delivered to you as of first importance what I also received: that Christ died for our sins in accordance with the Scriptures, that he was buried, that he was raised on the third day in accordance with the Scriptures, and that he appeared

(Note especially passages which emphasized that Jesus was NOT raised as a 'ghost', but with a physical body that could be seen and touched, and could eat... similar to the 1 Jn 1 reference above)

Luk 24:38-43 And he said to them, "Why are you troubled, and why do doubts arise in your hearts? See my hands and my feet, that it is I myself. Touch me, and see. For a spirit does not have flesh and bones as you see that I have."
And when he had said this, he showed them his hands and his feet. And while they still disbelieved for joy and were marveling, he said to them, "Have you anything here to eat?"
They gave him a piece of broiled fish, and he took it and ate before them.

Joh 20:24-27 Now Thomas, one of the Twelve, called the Twin, was not with them when Jesus came. So the other disciples told him, "We have seen the Lord." But he said to them, "Unless I see in his hands the mark of the nails, and place my finger into the mark of the nails, and place my hand into his side, I will never believe."
Eight days later, his disciples were inside again, and Thomas was with them. Although the doors were locked, Jesus came and stood among them and said, "Peace be with you."
Then he said to Thomas, "Put your finger here, and see my hands; and put out your hand, and place it in my side. Do not disbelieve, but believe."

3) Our great hope is the Resurrection of OUR BODIES, and connected to that, the restoration of CREATION!

Rom 8:19-24 For the creation waits with eager longing for the revealing of the sons of God. For the creation was subjected to futility, not willingly, but because of him who subjected it, in hope that the creation itself will be set free from its bondage to decay and obtain the freedom of the glory of the children of God. For we know that the whole creation has been groaning together in the pains of childbirth until now. And not only the creation, but we ourselves, who have the first fruits of the Spirit, groan inwardly as we wait eagerly for adoption as sons, the redemption of our bodies. For in this hope we were saved

2Pe 3:13 But according to his promise we are waiting for new heavens AND A NEW EARTH in which righteousness dwells.

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One other evidence of how the Gnostic scheme of "material"=bad, "spirit"=good (borrowing from the Greeks and Eastern thought generally) -- in Scripture, we find not only spirits that are (like God) righteous and good, but Satan and the demons who are EVIL SPIRITS... without bodies.