How you would react or your belief of what Christ would do is interesting, but irrelevant. You have the right to practice your religion as your conscience demands, but the baker has the right to believe differently than you do and come to another conclusion per his conscience.  

The issue isn't what Christ would do or what you would do or any other Christian who wants to bake the cake would do.  The issue is that some people believe the 1st amendment says you can't tell someone else HOW they should practice their religion.  SCOTUS needs to clarify if that's still true.

You implied that he's practicing his religion wrong & doesn't have the right to make the decisions he's made because he's theologically incorrect.  When you bring in what you would do, you imply your interpretation of religion is right & someone else's "wrong". 

Worse is deciding the law should support your interpretation & the law should tell him he's wrong. There's all kinds of problems with that method.