He is just saying in this, that these four things are a wonderful mystery which man cannot begin to understand.
Men look at the eagle flying through the sky and wish that they might fly, as well. There is no trace from where they came, or where they go, or even how they can stay up there in mid-air.
The amazing thing in this is how the snake slithers across a rock.
A ship in a large body of water leaves a mystery as to how it floats and how it finds its way to port.
The way of a man with a maid has been a mystery for all time. How two people destined of God to become one, can single each other out in all the mass of humanity, and find the mate so right for them that they will stay together until death do them part is one of the greatest mysteries to me.
If we were to look at these four things from a spiritual standpoint, we would see in the eagle the symbol of God. In the serpent, we see the symbol of Satan. We would see in the ship, the symbol of the church or the Christian on the sea of life; and we would see in the man with the maid, Christ and his bride (the church).
We see in this adulterous woman who covers her sin, a deception of not only deceiving others, but herself as well. Her heart is so hardened that she feels no guilt and shame.
Under Gods command 