You have not proved what was the first coming, and is already talking about the second. It seems to me that those who believe in God and not believe in science very poorly in school.
I also wants to say the same thing, but you told this. 
All the proof is in the writings in the Holy Bible. no human being needs to proof that. God send His only begotten son - Jesus, to come and save the world. Jesus offered Himself to die because of your sins so that you may be forgiven. It has already been done and it is up to you to decide whether to believe in His name or not. The birth of Jesus Christ was the first coming. On his second coming, He will take the righteous to Heaven and those who will be left will burn in an eternal inferno.