The notion than a person can know with certainty that he is saved and will join Jesus in heaven upon death has long been a fixture of Protestant and especially Evangelical theology.
Today, though, there are many voices who say that this is the height of presumption. How can we suggest that we know for sure what will happen to us after we die? Am I God? I don’t even know what I had for breakfast last week – how can I know my heart well enough to say I am surely saved?
Isn’t it dangerous to suggest that people can know they are saved – wouldn’t they take that knowledge and rest on their laurels rather than being about the work of the kingdom?
What if people think they’re saved and are wrong – isn’t it better for people to wonder and search rather than be wrongly assured of their safety?
You know, those are all good questions. The one problem is that assurance is totally biblical.
Confidence in our salvation is sprinkled throughout the Bible, but one apostle makes it particularly clear. “I write these things … so that you may know that you have eternal life” (1 John 5:13, emphasis mine).
But this isn’t what our friends worry so about; it’s not the easy-believism, pray a prayer and go on with your sinful life kind of assurance that, frankly, is rife in Evangelicalism today. Reading 1 John is like standing in front of a mirror. It will ask you to test how you live, how you love, and whom you love before it lets you walk away with assurance – and that is how it should be.
Assurance is biblical, but it's only for the believer who is willing to ask himself the hard questions. To that believer the Bible offers hope, security, and support through sickness, trials, and even his final moments on this earth – no mean treasure.
Still, though isn’t it presumptuous of us to suggest that we know what God thinks of us? Hardly. “It cannot be wrong to feel confidently in a matter where God speaks unconditionally, to believe decidedly when God promises decidedly, to have a sure persuasion of pardon and peace when we rest on the word and oath of Him that never changes” (JC Ryle, Holiness).
It is not presumption to rest on the promises of God.