1 John 5:5

Who is it that overcomes the world? Only he who believes that Jesus is the Son of God.

(v5, NIV)

It is the one believes that Jesus is the son of God who overcomes the world. It is only this person. There is no other person who will overcome the world. It is only the one who believes that Jesus is the son of God; this is why it says "only". The person who overcomes the world is not the person who is a "good guy", nor is it the person who is physically strong. Instead, it is the person who believes that Jesus is the son of God. Do you believe that Jesus is the son of God? Do you truly believe that Jesus is the son of God? Well, you will overcome the world.