Any question you or your friends in Sunday School have ever had about theology or Christology or doctrine was addressed in the first 500 years or so of Christianity, and all these questions were settled, and orthodox Christianity defined, by a long series of letters, debates, and councils.
A major review of orthodox Christianity and its practices was conducted beginning in the 1500’s (more or less), and all the significant questions were rearticulated and reaffirmed over a period of another 400 years or so.
The great minds in the first era are known as the Early Church Fathers. The great minds in the later era are known as the Reformers. At the end of the day, they agree (more or less) on the essentials.
The great minds who did all this thinking, debating, writing, counseling, and voting, are much smarter, wiser, and devout than you and me.
So it is wise for us to know them and read them.
Thanks.