Confidence has a great recompense of reward so dont throw it away (Hebrews 10:35)
If I were an enemy, what would my greatest attack be?
Create a fear that what God promised wont come to pass. That's why there is such a huge attack on pastors, tithing and the gospel. If more people have less faith in its accuracy and sincerity, then there will be less credibility thus less people will have confidence in the Word of God. Ever wonder why the serpent tried to get Eve to question what God said? It was getting her to doubt what God said so her confidence would be shattered.
The good news is that the devil cant take your confidence, just dont give it to him.
Don't be moved by what you see or sense in the physical realm, be moved only by the Word of God.
Maintain your stance in what you believe.