Hi there,

Could you please resubmit this question to be more specific about what you mean? Do you mean, why Christians came to believe that Jesus is God? Or do you mean, how did Jesus become God? If the first question, you should probably ask about the Council of Nicaea. If the second one--AskHistorians isn't the right forum for theological questions. You should try one of the Christianity subs, or maybe /r/AcademicBiblical.

Thanks!