Example of signs that reveal the nature, mind, and will of God:

Genesis 1:14 (NIV)
14 And God said, "Let there be lights in the expanse of the sky to separate the day from the night, and let them serve as signs to mark seasons and days and years,

Exodus 8:23 (NIV)
23 I will make a distinction between my people and your people. This miraculous sign will occur tomorrow.'"

Exodus 13:9 (NIV)
9 This observance will be for you like a sign on your hand and a reminder on your forehead that the law of the Lord is to be on your lips. For the Lord brought you out of Egypt with his mighty hand.