Revelation 12:15 shows the serpent, Satan, spewing a torrent of "water out of His mouth like a flood"! Aimed directly at the woman, that torrent is a diabolical and merciless attempt to sweep her away!
In John 7:38-39, water clearly represents God's Holy Spirit. This usage, in turn, has a direct connection to another usage important to this article and understanding Revelation 12:15-16. In this regard, Paul writes, "That He might sanctify and cleanse it with the washing of water by the word" (Ephesians 5:26), and Jesus adds, "It is the Spirit [which] gives life; the flesh profits nothing. The words that I speak to you are spirit, and they are life" (John 6:63).
Words, like water, have awesome power to do good or bad. They can give life like Jesus' words, or they can devastate and destroy like a flood of water when it is out of control.
Interestingly, Revelation 12:15 pictures this flood spurting from the serpent's mouth, the very place on the body where words emanate! This flood may someday materialize as a real army, but today Satan is inundating the world with such a torrent of appealing misinformation that some of God's people are being swept away. They are not yet lost because our God is more powerful than Satan, and He can save from the uttermost. But many are putting themselves into spiritual—and perhaps even physical—danger by being distracted from God's focus, the Kingdom of God.
John W. Ritenbaugh
The Flood Is Upon Us!