16Jesus answered them, and said, My doctrine is not mine, but his that sent me.
16Jesus answered, "My teaching is not my own. It comes from him who sent me. 17If anyone chooses to do God's will, he will find out whether my teaching comes from God or whether I speak on my own.
John 7; NIV - Jesus Goes to the Festival of - Bible Gateway;
Now the key part here is that "If anyone chooses to do God's will, he will find out whether my teaching comes from God or whether I speak on my own"
Note: In Context, the Will of God can't simply mean to follow Jesus, because that would make the entire statement logically flawed. It would read as "choose to believe in me and you will find out if you should believe in me.". Logically, it should be that someone should be making a choice to try and discern God's will.
This being taken to mean that anyone choosing to do Gods will will known if Jesus is telling the truth. Now, the problem here is people attempt to do God's will who both believe and disbelieve in Jesus. Now, the Jewish people certainly believe they are doing Gods will, they have chosen to do so and they think the Jesus does not exist. This creates somewhat of a predicament with the last line. Either
1. Every Jewish person in the last 2000 years has not chosen to try and follow Gods will.
2. Jesus is not from God, meaning his statements are not necessarily divine and true.
Expected rebuttals
The only one I can think of is covered in my Note. If Gods will is to believe in Jesus, then the entire statement would be logically flawed and would not make sense in the context. Jesus was talking to a group of Jewish people. He was saying to look to God to discern if Jesus's words are right or not. It would make no sense for him to tell the crowd to believe Jesus is doing Gods work before discerning if Jesus is doing Gods work.
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