Who said that it's moral to impregnate your own daughters and then blame it on them?
Also, pray tell how you know that all Lot's wife did was look back?
TF
2 Peter 7-8 Is clear that Lot was just and righteous:
And [God] delivered just Lot, vexed with the filthy conversation of the wicked: (For that righteous man dwelling among them, in seeing and hearing, vexed his righteous soul from day to day with their unlawful deeds;) 2 Peter 2:7-8.
So, to answer your question, it was God that said so.
You didn't use logic or reason to get into this opinion, I cannot use logic or reason to get you out of it.
You cannot over estimate the unimportance of nearly everything. John Maxwell
