In general, this world has both dark and bright sides. But the word "world" or cosmos referred to in the Bible is often related to the evil one. For example, Satan is called the king of this world, or the god of this world; unbelievers are considered worldly; the cravings of the flesh, the lust of the eyes, and the pride of life do not come from the Father but from the world.
Overcoming the world means overcoming the lusts of our sinful nature; the lust of our flesh, the lust of our eyes, and the pride of life are all temptations of the evil one.
Those "born of God" are those who are reborn in Jesus. Not only should Christians be baptized into Jesus Christ and have Christ's life within, they should live and walk in Christ Jesus by the power of the Holy Spirit. We must not become captives of this world. Rather, let us overcome this world—"and this is the victory that overcomes the world, our faith."
Whoever is born of God has a measure of faith that enables a person to overcome the world. Apart from acknowledging God's Word from within, faith includes trust and obedience. Trust is to grasp the promises of God and believe in His absolute power, while obedience is an affirmation of God's power and submission to all His commands.
Satan first attempted to make Eve fall by luring her to doubt God's word: "You will not die." Next Satan lured her to doubt God's love for her: "For God knows that when you eat of it... you will be like God" (Gen 3:4-5). God did not desire human beings to be as wise as He. In the end, Eve's failure to obey God's command led to the beginning of humanity's downfall.
May God help us and strengthen our faith to overcome this world. If we never doubt God's love or Word, and are willing to obey His commands daily as living and shining testimonies of Jesus' example of life—we will be victorious as God's people in this world. Amen!