"Alright fine, he was not a good human teacher. Why should I believe he was the Son of God and not a liar?"
The Bible contains many prophecies about the Messiah written hundreds of years before Jesus was born. These include when He would be born, where He would be born and how he would die.
Jesus fulfilled all of these propecies in his lifetime. Some he could contol, such as entering Jerusalem on a donkey, but many others such as being born in Bethlehem or being betrayed for 30 pieces of silver were completely beyond His control.
Beyond all the prophetic evidence, Jesus told his followers very plainly that he was the Messiah and the Son of God. Jesus knew that these were very difficult things to believe and so he performed many miracles to demonstrate the power and authority God had given to him.
These miracles alone do not prove he was the Son of God, for many prophets and even Jesus' own disciples were able to perform miracles.
However, one miracle in particular was more important than all the rest. Before he died, Jesus told his followers that he would rise again three days after His death. As He predicted, Jesus rose from the dead and emerged from the tomb on Sunday following His death.
This miracle is an important part of proving His identity, for it had been prophesied that the Messiah would not be taken by death. This miracle is unique, for no one else has ever been raised from the dead except those which Christ Himself and His disciples raised.
No other prophet has ever been able over come death the way that Jesus did. This special miracle tells us that Jesus was indeed who He said He was.
And so, all of Christianity rests on this miracle. If Christ rose from the grave and conquered death, then He is the Lord and Savior and Son of God. If not, then Christianity means nothing - it would be an empty lie. Even the apostle Paul recognized this when he wrote,
"And if Christ has not been raised, then all our preaching is useless, and your faith is useless. And we apostles would all be lying about God—for we have said that God raised Christ from the grave." 1 Cor 14,15a "
Son of God