Testimony - Come, see a man who told me everything I ever did.

At church, we are encouraged to give testimonies in the presence of fellow brothers and sisters, to give account of God's goodness in our lives.
Sometimes we have embarrassing moments when pastor gives an invitation to the congregation to come up to share a testimony and no one comes forward. Everyone either browses through the bulletin, pretends to pray, looks to the floor and gives those non-eye contact glares.

How come? What is a testimony? Is it a circumstance-based, an event-triggered happening in OUR LIVES, and God responded with some other (nice) happenings towards it? Is it a chain of "active" happenings or a "passive" discovery?

The woman went back to the town and said to the people, "Come, see a man who told me everything I ever did. Could this be the Christ?"

Nothing seems happening here.