In Genesis 18, Abraham, the father of faith, has had a meeting with God. His nephew, Lot, has been living in a place that God has revealed He is about to destroy. Abraham asks God, for the sake of the elect, if 50 righteous people live there, would You still destroy it? God says that He would not but the conversation whittles down to 10. If 10 righteous people live there, would God spare the city? God says He would. Lot has his wife, 2 daughters and they are both engaged to be married. The Lot family was 6. Could 4 more people be found? He only needed 10. Alas, not even 10 could be found, so judgement from God is coming. God, ever filled with mercy, sent angels to rescue Lot and his family.
The angels tell them to not look back, but Lot's wife looked back and turned into a pillar of salt.
As followers of Christ, may we not look back to the old life Jesus has delivered us from!