"God does not exist"

A group of people were discussing about God. One of them, probably disappointed, nervously said: "who is god? What is he? For me he does not exist at all. No, not at all! If he really exists, and if lie is so powerful, let him come down here and slap me. Let him do so. Let him prove that lie does exist". He laughed-boastfully and after a few minutes, he continued: “you see, God does not exist.”
Then, he left the group to go home. While, crossing the road, a tall young man who was passing-by on his motorbike avoided him and fell off. He stood up, went straight to the man and slapped him on both cheeks. The man fell down and fainted. Does God exist?

Vocabulary

To aint: s'évanouir    
To slap: giffler
To fall off a motorbike: tomber d'une mobylette    
Boastfully: en se vantant