2 Corinthians 12:10 (NWT) Therefore I take pleasure in weaknesses, in insults, in cases of need, in persecutions and difficulties, for Christ. For when I am weak, then I am powerful. (Other versions)
At times we may feel apprehensive or inadequate in our ministry, especially when we are challenged to defend our beliefs by people we meet. Still, Peter encourages us to "sanctify the Christ as Lord in your hearts, always ready to make a defense before everyone that demands of you a reason for the hope in you, but doing so together with a mild temper and deep respect." (1 Peter 3:15) (Other versions)
So, coming back to Paul’s words, what we can learn is to not be afraid to be "weak". In other words, be willing to put ourselves in an uncomfortable situation so that the spirit of God can be our power and not our own learning and abilities. The fact is that the best potential new believers come from those that were adamantly opposed because these tend to research more diligently. For example, Paul himself was a persecutor of the early congregation of Christians. So don't shy away from challenges. You may actually have found yourself a new future brother (or sister) in the faith.