John 9 is a long chapter, and most of it is not about the healing. It is about what happens afterwards. The neighbours argue, the Pharisees interrogate, the parents back away. Everyone has a theory about Jesus. The man who was healed has only his experience.
He does not pretend to know more than he does. Asked if Jesus is a sinner, he says he does not know. What he knows is simple and cannot be taken away: I was blind, and now I see. Under pressure, his faith gets clearer, not weaker. He is thrown out for it, and Jesus comes looking for him.
We do not need to win every argument about faith. We do need to be honest about what God has done for us. A young person asked hard questions at college, or an adult mocked at work, can still say: this is what I know. That kind of witness is quiet, but it is very hard to argue with.