Why do we need to have an assurance of our salvation?
In studying and proclaiming the gospel, this question has been asked of me, and, in fact, I have asked this question myself. It is not a bad question because one of the fundamental reasons for it is the prevalence of false assurances. To give anyone a false assurance is to mislead them and be guilty of lying, and to be falsely assured is awful. And so we ask, “Why bother with it?”
The trouble here is that the need for assurance comes built-in in us. We need it for purpose, hope, endurance, and many other aspects of life. So I think the question that better understands the concern is not why we need it, but whether or not we should have and give assurance of salvation.
Supporting this question is the desire to simplify Christian doctrine for clarity. It goes something like this: assurance is complex and multifaceted, and cannot be universally applied—therefore we are always in danger of applying it wrongly, and so we are better off silent. While this is a healthy fear, it should not cause silence. Rather it should drive us to acquire a broad understanding of the topic.
There is also another reason why this concern is brought up—and this seems to be the most common concern. It is a concern that has plagued the Church for some time now, and one of the best places to observe it is in the 16th Century with the Reformers and the Catholic Church. They both had different answers for two assurance-based questions: Can I know I'm saved? And if I'm saved, can I lose my salvation?
To the first question, the Catholic Church said, "Maybe," while the Reformers gave a resounding yes! To the second question, the Catholic Church said, "Certainly," while the Reformers said, "Never!" Did the Reformers simply want to do exactly the opposite of the Catholic Church, or was there a better reason?
The reason for the Reformers’ answers was simple—it was plain for all to see in Scripture. On the other hand, the Church's reasoning was more complex.
If you understand Catholic doctrine, you will understand how they got to their answers. Ever since the Great Schism of 1054 when the Eastern Orthodox Church split with the Western Orthodox Church, the primary doctrinal concern of the West (Rome) was justification. The question most on their minds was how man could be right with God. Rome concluded that obedience to the moral law and receiving the sacraments made one right with God. They believed this to be a process where they ever and always progressed in their righteousness. To have complete assurance that a person attained justification was nearly impossible since there was always progress to be made. That meant their answer to the question of assurance ended up sounding something like this: "You cannot completely know you are saved, and you are ever in danger of losing your salvation, so then you must continue in obedience and receiving the sacraments."
There are many today who hold to a similar belief. They fear that assurance will cause complacency in the believer's life towards holiness. They fear that the promise of never losing salvation will cause many to plunge headlong into sin, assured that they could sin all they want without falling away. And so they teach a guilt-ridden assurance; an assurance based upon the good works of the believer, able to be lost whenever that believer sins or backslides. This leaves the believer in the same mess as before, always unsure if they measure up to God's standard, never certain that their decision for Christ is true. It is a manipulative, works-based assurance. It is a guilty assurance.
The cure is found in Christ. When Paul writes to the Corinthians that in Christ we obtain "wisdom from God, righteousness and sanctification and redemption" (1 Cor. 1:30), he is communicating to them that there is absolutely nothing they can do to add to their salvation. In essence, Paul is claiming that absolutely nothing will help their assurance of salvation if they are not assured of Christ. Christ is our righteousness—our right standing before God. Christ is our sanctification—our growth in holiness. Christ is our redemption—the entire work of salvation. Therefore, for any Christian to look outside of Christ for their assurance is to act in an opposite manner to their life title of "in Christ."
Furthermore, when the fear of misusing grace for the purpose of sin arises, Christ is our cure once again. Paul has certain Romans in mind when he writes, "What shall we say then? Are we to continue in sin that grace may abound? By no means! How can we who died to sin still live in it?" (Rom. 6:1-2). These Christians thought that the abundance of grace gave freedom to sin, but such is certainly not the case. The answer to the question was not, "Try harder not to misuse it." Rather, Paul expounds the benefits of Christ. He goes on to explain, "We know that our old self was crucified with him in order that the body of sin might be brought to nothing, so that we would no longer be enslaved to sin" (Rom. 6:6). The reason grace must not be abused in not because we must work for it, but because Christ gives life freely! Therefore, Christians need not worry about abusing the assurance found in Christ because Christ brings freedom from sin.
To conclude, any assurance we may find outside of Christ will never contribute positively to our salvation. It will only be an assurance in self, or in the Church, or in another believer. All these will fail. Christ cannot fail. Therefore, let us go to Christ for our assurance. There, we will never be motivated by guilt or fear, but will be embraced with life, love, hope, and peace.
Blessed assurance, Jesus is mine; Oh, what a foretaste of glory divine! Heir of salvation, purchase of God, Born of His Spirit, washed in His blood.