20 Then God said, "Let the waters swarm with fish and other life. Let the skies be filled with birds of every kind." 21 So God created great sea creatures and every living thing that scurries and swarms in the water, and every sort of bird-each producing offspring of the same kind. And God saw that it was good.
Matthew Henry's Commentary on Genesis 1:20-21
Commentary on Genesis 1:20-25
(Read Genesis 1:20-25)
God commanded the fish and fowl to be produced. This command he himself executed. Insects, which are more numerous than the birds and beasts, and as curious, seem to have been part of this day's work. The Creator's wisdom and power are to be admired as much in an ant as in an elephant. The power of God's providence preserves all things, and fruitfulness is the effect of his blessing.