Hebrews 11:7 MSG - By faith, Noah built a ship in the middle of dry land. He was warned about something he couldn’t see, and acted on what he was told. The result? His family was saved. His act of faith drew a sharp line between the evil of the unbelieving world and the rightness of the believing world. As a result, Noah became intimate with God.
"He was warned about something he couldn’t see". He could have ignored the warning because he couldn't see what was coming. There was no sign of rain when Noah was instructed to build the ark. There hadn't been for quite a while. Why do you need a boat with no water?? The people thought he was nuts! I'm sure he even questioned the instruction. But, he pushed past what "made sense", he trusted God and his obedience saved his family.