“Then God said, ‘Let the waters teem with swarms of living creatures, and let birds fly above the earth in the open expanse of the heavens.’” (Genesis 1:20, NASB)
The command of God continues to organize and establish. Life is created here, not only living and breathing but moving. The waters are now filled with life. The phrase “teem with swarms” can also be translated “swarm with swarms”. The structure of the phrase is called a cognate construction. It emphasizes the abundance of life commanded for the waters of the earth. The same large amount of life is also emphasized concerning the birds. It is the Polel form of the verb, used to stress the abundant life God gives.
The sky was created in 1:7-8, when God knowingly prepared a place for the birds. The same was done when He organized the sea and land. Each day of creation is leading up to the creation of mankind, that we should glorify God for His preparation as well as His continued blessing. With prior knowledge God prepared the earth as a home to support life.
Though every type of sea creature and bird was created on the fifth day, this is not an exhaustive list. It would be unprofitable for God to explain what can be discovered in our lives. Science is fairly successful in documenting all of God’s creatures. Their mistake is organizing them in an evolutionary fashion because they deny the things God has revealed, both in nature and in the Bible. The Bible reveals those things we could not discover without God’s help. Thankfully God supplied us with this revelation. In it He not only discloses the beginning of life but the importance of life, the nature of man, the explanation of man’s condition and finally our only hope of finding a home for eternal life – through God Himself.