If you consider how Israelite religion amassed into a nation, you're investigation will reveal that polygamy facilitated its rise; I mean, Jacob had four wives from which all his sons were born.

Pertaining to the #Mormon religion, #JosephSmith simply restored this practice. And, yes, I'm aware that monogamy is the norm according to #thebookofmormon . But when necessity arises, polygamy becomes requisite.