Noah's decision to build an ark required a supreme act of faith. There was no body of water nearby. In fact, it had never rained on Earth before. At that time, God had placed a water canopy over the planet that created a greenhouse effect of sorts. So in one of the greatest acts of faith in human history, Noah cut down his first gopher tree to start building the ark.
It was such a bold act of faith that Noah was memorialized in Hebrews 11, known as the Hall of Faith: "By faith Noah, being divinely warned of things not yet seen, moved with godly fear, prepared an ark for the saving of his household, by which he condemned the world and became heir of the righteousness which is according to faith" (verse 7).
This verse gives us a number of important insights into what made Noah tick. First of all, we read that he was "divinely warned." God spoke to Noah. Romans 10:17 says that "faith comes by hearing, and hearing by the word of God." Your faith will grow when you read what the Bible says and then take the next step and put it into action.
We also read that Noah "moved with godly fear." Noah had a reverence for, or a fear of, the Lord. And a good definition I have heard for the fear of the Lord is "a wholesome dread of displeasing Him."
Noah's walk with God caused him to work for God. And one must always precede the other. If you walk with God, you will want to work for God. Works don't save you; faith does. But if your faith is real, then it will produce works. That is how Noah's faith worked when God told him to build the ark.