They don't know really. Honestly I do not think alot of the messangers and prophets. Why? Because they don't have a living legacy. I am talking about Godly guidance. God knows what would guide me. And no I am not expecting for an angel or money to fall from the sky.
There was a town with a beautiful church within a valley. One day it started to rain. It rained so much that flood alerts were issued. By the next day all the ground floors of every house was flooded and fire trucks were taking people to safety. The fire trucks went to the Church to get the Minister, but he said "My God will save me".
By the after noon the trucks couldn't enter the town and so, boats were sent to get the rest of the people, When the boats arrived at the church, the Minister said "My God will save me, go away".... come evening, the flood waters had engulfed ever house and was now reaching the top of the Church. The Minister had taken to the roof and was holding onto the spire for dear life when a rescue helicopter lowered its rope and a man came clambering down "Take a hold of this harness and clip it to your clothing and hold on"... but the Minister replied with "No, go away, My God will save me". So the helicopter left and the Minister ended up drowning.
When God raised the Minister alive, he asked God angrily "Why did you not save me? I believed in you?"... you know what God returns with?
"I sent you emergency vehicles, boats and even a helicopter - what were you expecting? Can you not read the signs I left for you? You? A Minister of the faith?"
- this story is all about the OP and his inability to "SEE" those signs.
Not to mention he is still a child going through puberty... lol that makes me giggle.