In today's reading, Jesus throws in one of those phrases that we should really listen to. He tells us that when our adversaries speak against us and ridicule what we say, not to worry about what answer we shall give, the Spirit shall speak in us.
Fortunately, few of us shall be put in legal or life threatening situations where we shall need this immediate help of the Spirit. However, as we in the Church come under more and more attack, we will be called on to defend her. We must ask the Spirit for guidance in what to say and how to answer.
The hatred of the world for the Church is immense. Against this hatred we feel so small and insignificant.
We worry about what we would say or do if certain circumstances arise. We shouldn't. If God lets the situation arise where we shall have to defend the Church, then he shall also give us the words, through the Holy Spirit to do so. We need not worry. Trust is part of our faith.