In Facing Fear, I discuss some basics of Hebrew grammar and briefly address the Old and New Testament teaching on fear and courage. While there was not space to include all that Scripture mentions about cowardice, the following is just a brief discussion of a key verse often cited related to Biblical teaching on cowardice.
It is commonly taught that cowardice is sin and worthy of hell. This teaching likely comes from Revelation 21:8,
“But for the cowardly and unbelieving and abominable and murderers and immoral persons and sorcerers and idolaters and all liars, their part will be in the lake that burns with fire and brimstone, which is the second death.” (NASB)
What are we to make of this? Is this verse directed towards the Christ-follower?
Biblical Lists of Sin
The Bible includes several lists of sins, starting with the Ten Commandments and then many more lists in the New Testament. In the book of Revelation, “there are two parallel vice lists [to 21:8] in 9:20–21 and 22:15.”
Interestingly, the words “coward” and “unbeliever” are found in no New Testament list, except here in Rev 21:8. Aune states,
The term “cowards” here seems to be intentionally used as the antonym of “the conqueror” in v 7a.
In other words, the conqueror is the Christ-follower whereas the coward is the one who never follows Christ as Lord. A question worth considering is “What does the Christ-follower conquer in the context of Revelation 21?”
Cowardice through a Greek Lens
It was missionary and British theologian, Lesslie Newbigin, who discussed how we in the West do not question our cultural assumptions, just as a fish doesn’t “know” the water they are swimming in.
To see our own culture, how might we subconsciously use an ancient Greek lens when thinking about fear, courage, and even cowardice? When we read the Bible in the twenty-first century, are we uncritically mixing what Plato or Aristotle said about fear and courage with what the Bible actually says in the Greek or Hebrew text? For Plato, cowardice is an immoral action of bad men. But for Christ-followers, we want to live according to how God defines “good” and “bad.”
It is always unwise to pluck one word out from a verse and make an application without considering the surrounding context. When we look at the context of Revelation, several observations stand out. In Revelation 9:21, 21:8, and 22:15, lists of sins are given, and all three lists seem to describe the qualities or actions of those never professing faith and never submitting to the one true God.
Cowardice, in the context of Rev 21:8, marks the person who so fears the powers of this world they refuse to submit to the one true God and Christ Jesus the Messiah. Thus, it is a misapplication to apply “cowardice” (in Revelation 21:8) to the believer. This verse describes the type of people who totally reject God.
To be sure, Christ-followers, both in the Bible and today, may be found guilty of those sins listed in Revelation 21:8, yet through Jesus Christ, the Son of God, we have peace and reconciliation with God. His merciful lovingkindness is deeper than we can comprehend. Nothing can separate us from his love. We see throughout the Bible examples of cowardice in God-fearers, including Adam, Moses, Jonah, King Hezekiah, Peter, John Mark, and many, many more.
Fear is an opportunity.
The Christ-follower is repeatedly exhorted not to be overwhelmed by fear but instead obey him despite our fear. When we feel the temptation to allow fear to paralyze us, we also have the opportunity to choose obedience. Obedience is acting in courage despite our fear.
Our Lord is far more gracious than we often realize. When he asks us to go to dangerous places for His sake, he knows what fears will arise in us. He wants us to bring our fears to him, and he will give us boldness and courage, one fear at a time. His faithfulness to do this sustains us.
 Lesslie Newbigin, Foolishness to the Greeks: The Gospel and Western Culture (Grand Rapids: Eerdmans, 1986), Kindle Location 273.