I recently wrote a blog on the NT concept of overcomers (see here). That blog led to this question: 

The problem with this logic is that Revelation 2:11 does not make sense if only victorious Christians are overcomers.  I need you to address this verse specifically: “‘He who has an ear, let him hear what the Spirit says to the churches. He who overcomes shall not be hurt by the second death.’” Are you suggesting that only victorious Christians who endure in good works will escape the second death? 

Actually, several of the seven letters of Revelation 2-3 have puzzling statements that can be [wrongly] interpreted to mean the non-overcomers will be eternally condemned. (See this May 2018 blog which briefly covers all of the overcomer passages in Revelation 2-3.) Revelation 2:11 is one such verse. But it doesn’t really imply that non-overcomers will be eternally condemned.  

What the Lord says is that the overcomers won’t be hurt by the second death. This is clearly an understatement. The overcomers will be greatly rewarded. Every believer knows that overcomers won’t be eternally condemned. John 3:16 and 5:24 make that clear. So does Rev 20:15.  

One key to Bible study is to carefully consider the context. Verse 11 is the end of the second letter. So the following verses are no help since they are part of another letter. But the preceding verses can help us understand v 11. In particular, note v 10: “Be faithful until death [= overcome], and I will give you the crown of life.” The crown of life here is fullness of life in the life to come. It is a reward.  

Gaining the crown of life in v 10 is equivalent to the understatement in v 11 of not being hurt by the second death.  

In a March 1991 article (see here), Zane Hodges wrote, “Revelation 2:11 is not a veiled threat that the unfaithful believer may forfeit eternal life. On the contrary, it is an effective litotes  [understatement] whose very vagueness stirs our imaginations and our hearts with anticipation.” 

In our two-volume commentary on the NT, Bob Vacendak explains Rev 2:11 in this way:  

Turning to an application for all the churches, Jesus states that He who overcomes shall not be hurt by the second death. Arminian commentators err in taking this verse to mean, “Believers who do not overcome shall be hurt by the second death.” Reformed commentators also err by reading it this way: “All true believers are overcomers and therefore will not be hurt by the second death.” Both views have Jesus offering escape from hell for faithful obedience to Christ. Since this flatly contradicts so many passages regarding eternal security and justification by faith alone (e.g., John 5:24; 10:27-30), it is better to understand Jesus’ words as a figure of speech called litotes.  

Litotes is an assertion that understates the reality being referred to…A Biblical example of litotes is Heb 6:10: “God is not unjust to forget your work and labor of love which you have shown toward His name,” meaning God will definitely remember all your hard work. 

So, when Jesus says, He who overcomes shall not be hurt by the second death, He is making an understatement. He is saying that the faithful Christian will be more than amply repaid for whatever sacrifice he may make for Christ’s sake, and that his eternal experience will be so far beyond the reach of the second death that it cannot be imagined. The suffering believers in Smyrna could rest in this glorious promise given to them from the Lord Himself (The Grace New Testament Commentary, Vol. 2, s.v. “Revelation,” p. 1262). 

Overcomers will be highly exalted. That is the point of Rev 2:11.