Everyone has a message he or she needs to share.
There’s a saying in church circles that everyone has at least one sermon in him. What I mean when I use the expression is that each person, no matter how long he or she has been a Christian, is passionate about at least one thing, one topic. Each person has a message which he or she feels other Christians, or the church as whole needs to hear.
The message might be a very positive one, for example, an aspect of God’s blessing or His grace which this person understands or has experienced more than others. It might be a message of encouragement and hope when others are in despair. It might be a message of comfort in the face of distress and grief. It might be a message to motivate. Or, it might be a message of rebuke to the complacent or those who are drifting away.