"With the coming of dawn, the angels urged Lot, saying, 'Hurry! Take your wife and your two daughters who are here, or you will be swept away when the city is punished.' When he hesitated, the men grasped his hand and the hands of his wife and of his two daughters and led them safely out of the city, for the Lord was merciful to them." NIV translation
We see that Lot hesitated to leave even in the face of destruction. Whether it was because he cared about the people that would be left behind or whether he was concerned about material things and his political position, we do not know.
"As soon as they had brought them out, one of them said, 'Flee for your lives! Don't look back, and don't stop anywhere in the plain! Flee to the mountains or you will be swept away!'" NIV translation
The angels gave Lot and his family instructions for their survival. The instructions are a good reminder for us that, when we come to Christ, we are to leave the old life behind. We are to come in repentance and flee the old as we grab onto the promises of God. Just as the angels guided Lot, we have the Holy Spirit to guide us in our journey.
"But Lot said to them, 'No, my lords, please! Your servant has found favor in your eyes, and you have shown great kindness to me in sparing my life. But I can't flee to the mountains; this disaster will overtake me, and I'll die. Look, here is a town near enough to run to, and it is small. Let me flee to it - it is very small, isn't it? Then my life will be spared.' He said to him, 'Very well, I will grant this request too; I will not overthrow the town you speak of. But flee there quickly, because I cannot do anything until you reach it.' (That is why the town was called Zoar.)" NIV translation
Lot did not see how he and his family could run all the way to the mountains for safety and so he begged the angels to spare a little town called Zoar. They granted his request and we are reminded that God only asks us to do what we can and He will do the rest.
Like Lot, many Christians walk around in fear that they still will not make it to heaven because they do not act perfectly. We are reminded that God spared the little town because that was where Lot and his family were going to be. Jesus has saved us where we are and He does not want us to fear the coming destruction.
"By the time Lot reached Zoar, the sun had risen over the land. Then the Lord rained down burning sulfur on Sodom and Gomorrah - from the Lord out of the heavens. Thus he overthrew those cities and the entire plain, including all those living in the cities - and also the vegetation in the land." NIV translation
When Lot reached Zoar, the judgment began with the raining of sulfur on the plain. The evidence suggests that God caused massive earthquakes which released tar and gases from the ground as the cities were located in an area with tar pits. The tar and gases exploded and rained back down on the earth in fire.