I saw Satan fall like lightning from heaven

Why Satan fall like lightning from heaven?

When the disciples brought the ministry report, the report was filled with self righteous and self proclamation - And he called the twelve together and gave them power and authority over all demons and to cure diseases, and he sent them out to proclaim the kingdom of God and to heal. And he said to them, Take nothing for your journey, no staff, nor bag, nor bread, nor money; and do not have two tunics. And whatever house you enter, stay there, and from there depart. And wherever they do not receive you, when you leave that town shake off the dust from your feet as a testimony against them. And they departed and went through the villages, preaching the gospel and healing everywhere  - Luke 9:1-6

On their return the apostles told him all that they had done. And he took them and withdrew apart to a town called Bethsaida - Luke 9:10

And when the disciples rely on their own power or self righteous it became a snare for them and brought failure in their life, but our Lord is full merciful, he never leaves us nor forsakes us, but he keep molding us for his kingdom.

from their failure and learning, the disciples understood that Lord Jesus Christ is doing all the wonderful things in our life, and they could confidently Pray in the name of Jesus Christ - After this the Lord appointed seventy-two others and sent them on ahead of him, two by two, into every town and place where he himself was about to go. And he said to them, The harvest is plentiful, but the laborers are few. Therefore pray earnestly to the Lord of the harvest to send out laborers into his harvest. Go your way; behold, I am sending you out as lambs in the midst of wolves. Carry no moneybag, no knapsack, no sandals, and greet no one on the road. Whatever house you enter, first say, ‘Peace be to this house!’ And if a son of peace is there, your peace will rest upon him. But if not, it will return to you - Luke 10:1-6

The seventy-two returned with joy, saying, Lord, even the demons are subject to us in your name! - Luke 10:17

When the disciples started acknowledging Lord Jesus Christ they experienced the Joy of Lord, their is no place for Satan in our life - And he said to them, I saw Satan fall like lightning from heaven - Luke 10:18