Proverbs 30:18-19

Agur did not know how these things move. They move smoothly in places where it is difficult to move. And these things leave no trace as they move. So Agur considered that they were great mysteries.

• He did not know how a bird flies through the air.

• He did not know how a snake could move without legs on a smooth rock.

• He did not know how a ship sails on the sea.

• And he did not know how a man loves a woman. This is not like the other things in this list. But love between a man and a woman is also a strange mystery.