for "Everyone who calls on the name of the Lord will be saved. How, then, can they call on the one they have not believed in? And how can they believe in the one of whom they have not heard? And how can they hear without someone preaching to them?
1 Corinthians 15:14
And if Christ has not been raised, our preaching is useless and so is your faith.
2 Timothy 3:16-17
All Scripture is God-breathed and is useful for teaching, rebuking, correcting and training in righteousness, so that the man of God may be thoroughly equipped for every good work.