So why a book about "Eternal Security"? Aren't there plenty, one might ask, or is this another Calvinism vs. Armenian book? My answer comes both as a pastor and, hopefully, a balanced Biblicist opposed to both Calvinism and Armenianism extremes.
In fact, both sides in years gone by have referred to the issue as "Assurance of Salvation." For the Calvinist, assurance is reached by rising to a level of spirituality. One then recognizes that you are preserved by the grace, provisions of the Lord's enablement apart from your works. However, your works must prove it. This, of course, is part of their view of predestination and regeneration. For the Armenian, one is also preserved by grace and some human efforts, which one could sin or backslide enough and lose. This then is the evidence of unbelief or fallen grace.
As a pastor, the following can be seen by those who struggle with the concept of eternal security or full assurance. First, there is a level of joy and peace never fully realized. Second, there is the insecure life with a level of constant fear or guilt. It is like a child on a bike being chased by an angry dog. You are always looking over your shoulder to see if some sin, failure, or imperfection is going to catch you. You must keep peddling harder. Finally, there is the unconscious doubt that surfaces. The "am I good enough for God; am I doing enough for God; am I pleasing God enough?" Oh, the emptiness and misunderstanding of His unmovable love which escapes the doubter!
The issue of being Forever Forgiven, Forever Secure, "Forever His" is paramount to "growing in grace and in the knowledge of Jesus Christ" 2 Peter 3:18. It is much deeper than accepting a propositional theological truth concerning one's salvation. It is more than being a separated (sanctified) believer. Your personal eternal security is the groundwork for a relationship with Christ, our husband, that is the wellspring of an overflowing abundant life. It becomes the joy of liberation in Christ.
So, let us consider the why and the benefits of being "Forever His".