he was a combination of Jesus and Samson, the two thought that the stories in the bible were good layouts for a superhero story and went with it.
This is why they feature
-A heavenly figure sending his only son to earth while in distress
-The son being adopted by a good natured but poor couple.
-The son growing and realising his effect on the world around him
-His trek into the Deseret to meet his father in spirit for the first time and be given a direction of helping others
-upon reaching adult hood he goes acts out on his fathers wishes and begins to help others.
And then all the powers came from Sampson, which makes more sense when you realise originally he couldnt even fly, just jump really high, and didnt have just as many exaggerated powers.
And then you need to consider the time period it came out and the personal issues they were going through at the time (Shusters father got shot by a mugger).