Let me explain my understanding of this passage. When Jesus heard this, he said, This disease will not die, but will glorify God, so that the Son of God may be glorified. My understanding is that this patient is sick because God wants Jesus to heal him, so that people who see him can believe in him and trust him. People believe that the son of God is glorifying God, and Jesus can cure his illness because of the power God has given him. This authority was given to him by the father, so we should glorify God.
In the final analysis, we should trust God in everything and glorify God in everything.
The sick man gave God a true witness, or the reason why he was sick was to give God a witness.
Things like this are happening now, but Jesus didn't appear in the form of flesh and heal them, but they really got better. These are not what I saw with my own eyes, but what I heard from my brothers and sisters in the church about their personal experiences.
However, I also have examples that can testify for Jesus, but I am not sick. Every Christian testifies in different ways, because God has different plans for everyone. My testimony, in my Baidu space, you can have a look if you are interested.