Genesis 7:6, 11 (NRSV)

[6] Noah was six hundred years old when the flood waters came on the earth... [11] In the six hundredth year of Noah's life, in the second month, on the seventeenth day of the month, on that day all the fountains of the great deep burst forth, and the windows of heaven were opened.

I have no idea how to even conceptualize being alive for 600 years, other than to assume that I would be pretty tired and more than a little bit cranky. 

But not Noah.

God put Noah to work by having him build an ark when there was NO evidence to suggest that there would even be a flood. And just when there was plenty of room to doubt that what God said would happen would actually come to pass, the windows of heaven were opened.

Do the work.  Trust God.  Watch the windows of Heaven open in your life.