The Word of God keeps us from sin. Apostle Paul admonishes us to be transformed by the renewing of our minds. (Romans 12:2) The Word of God is our instruction manual that teaches us how to live a life that is pleasing to God.
Studying our Bibles equips us to resist the devil. We must always be ready to give an answer to his tricks with the Word of God. When Jesus was tempted by the devil in the wilderness, He answered every instance of temptation with the Word of God. By quoting scripture right back to the devil, Jesus resisted him and eventually Satan left. (Luke 4:1-12)
And take the helmet of salvation and the sword of the Spirit, which is the word of God. Ephesians 6:17
A Powerful Weapon!
The Word of God is also a powerful weapon with which to fight the devil. We should read our Bibles daily to be skillful in using our weapon.
For the weapons of our warfare are not carnal, but mighty through God to the pulling down of strongholds; casting down imaginations and every high thing that exalts itself against the knowledge of God, and bringing into captivity every thought to the obedience of God; and having in a readiness to revenge all disobedience when your obedience is fulfilled. 2 Corinthians 10:4-6