The story of Noah is wonderful. He demonstrated great faith, and God completed an amazing work through him. However, his life has a very disappointing end. Noah got drunk and cursed one of his sons.
If we understood the nature of spiritual warfare, the reason for Noah’s failure would be obvious.
Where were the spiritual powers of evil before the flood?
They were spread out across the world causing the people to sin and do evil.
Where were they after the flood?
Some had been captured and were bound, but the rest joined together to attack Noah. Under such a staunch spiritual attack, he did not stand a chance, as he was totally outnumbered. We should not judge him for his failure.
God waited for another opportunity. By the time of Abraham, the population of the world had massively increased, so the spiritual powers of evil had to spread themselves out across the world. God called Terah and Abraham his son. Because they were moving away from the centre of political power in Ur, they were not noticed by the powers of evil.