The assurance of which Scripture speaks and which believers and their children have, and ought to have, is certainty. It is certainty about God, about the spiritual things made known in the Bible, and about salvation. Another word for this spiritual state of the soul of the believer and child of believer is confidence.

This certainty is absolutely sure. There are no degrees of certainty, as though there can be certainty that is 75% sure, but 25% unsure, and certainty that is 90% sure, but 10% unsure. If certainty is not 100% sure, it is no longer certainty, but uncertainty, that is, doubt.

The opposite of certainty is not partial certainty, but doubt. Doubt is uncertainty.

If you and I are walking in mountains with which I am familiar, and we come to a wooden walkway over a deep ravine, and you ask me, “Are you certain that the bridge is strong enough to bear our weight?” you do not mean, “Are you 75% sure?” but, “Are you fully confident?” And if I respond, “I am 75% sure of the bridge,” you do not walk across the bridge with glad hosannas about my partial certainty, but you stay off it because of my doubt.

There are reasons why a believer is sometimes uncertain about his salvation, why he finds himself miserably doubting, but the reason is not that assurance itself is uncertain. Rather, the uncertainty of his sinful nature, or the doubt instilled into his soul by the devil, or even a lack of certainty that is a judgment of God upon him has temporarily eclipsed his assurance.

Full Assurance

When we read in Hebrews 10:22 of “full assurance,” we must not suppose that the reference is to assurance that is finally 100% in distinction from assurance that used to be only 50%, because in the past it was accompanied by 50% doubt. The apostle exhorts us who believe the gospel from the heart to draw near to God in assurance, which is always full assurance, and can be nothing else but full assurance. And this assurance, which is by the very nature of assurance full, belongs to faith: “full assurance of faith.” The Geneva Bible, great predecessor of the marvelous King James version, did not even use the word “full” in translating Hebrews 10:22, but spoke simply of “assurance”: “Let vs drawe nere with a true heart in affurance of faith.” The King James translators chose to make explicit what is implicit in “assurance” and added “full.”

That assurance is certainty is of the greatest practical importance. The Puritans of whom I spoke in the previous editorial, and those influenced by them, are confused about this. They speak of “full assurance” and the search for full assurance as though one can have partial assurance, which then, by ardent seeking, may become full assurance. The consequences of this confusion are disastrous. It fills churches, Reformed in name and confession, with members who, although they profess to believe the gospel, have only “partial assurance,” that is, members who are profound doubters.

The opposite of full assurance is no assurance.

It is as erroneous to contrast full assurance with partial assurance, as it is to contrast full faith with partial faith.

Assurance can and must grow in us, just as our faith can and must grow. But the growth is not from partial to full, from 10% to 100%. Rather, assurance, like the faith of which it is an integral part, develops (under good, sound, healthy, doctrinal, expository, Reformed preaching!) from a principle—a beginning—to maturity. The example is not filling up a glass of water that was half-full—and half-empty. But the example is the growth of a seed, which contains everything the plant will be, into a mature plant.

Certainty about Scripture

That about which the child of God can be, is, and ought to be certain—absolutely certain—includes several things. First, he is assured that Holy Scripture is the inspired Word of God. Because Scripture is the inspired Word of God, it is reliable. Upon it the believer can and does depend. This certainty is fundamental to all the other aspects of assurance. If I do not know and trust Holy Scripture as the wholly divine, inerrant Word of God, if I have doubts about Scripture, I must have doubts about all that it teaches, including Jesus Christ the Savior, faith in Him as the alone way of salvation, my own salvation, and the future salvation that Scripture promises.

The reason why doubt is widespread in liberal Protestant circles, as in evangelical churches and seminaries that have succumbed to the same modernist malady but are not yet quite so far along in the process of dying, is unbelieving criticism of the Bible as merely a historical, human document—the fallible words of men.

I do not say more about this aspect of assurance, for this is not my main concern in these editorials. But I remind us that certainty about the Bible is the foundation of all assurance, including that aspect of assurance that is the main concern of these articles, namely, assurance of salvation. “All scripture is given by inspiration of God” (II Tim. 3:16). Of this, believers and their children are sure—absolutely sure.

Certainty about Jesus Christ

Second, believers and their children are assured that Jesus Christ is the Savior—the only Savior—from sin and death and woe appalling by His incarnation, His atoning death, and His bodily resurrection. Implied is our certainty that our misery is the guilt of our sin in the just judgment of the holy God.

Also this aspect of the assurance of the child of God is, and must be, an undoubted certainty. Surely, no Christian will allege that his assurance that Christ is the one and only God-appointed Savior is 75% certainty and 25% uncertainty. The Christian is absolutely certain that Jesus Christ, as the Son of God in human flesh, is the only Savior of sinners.

So basic is the assurance that Jesus is the only Savior that without it there can be no assurance of personal salvation. Besides, one who lacks the assurance that Jesus is the Savior really does not have the certainty that the Bible is the inspired Word of God, for the message of the Bible is that Jesus is the Savior.

Nevertheless, doubt that Jesus is the Savior can creep into a church. Against this doubt, the author of the epistle to the Hebrews was fighting. Some of the Jewish members of the early church were inclined to observe again the Old Testament sacrifices, ceremonies, and worship as necessary for their salvation. This was the “wavering” and “drawing back” noted with alarm in Hebrews 10. Professing Christians, members of the churches, were wavering with regard to Jesus Christ and were drawing back from Him. They were beginning to doubt that He is the one and only Savior.

Still today, wherever the teaching enters a church, that in addition to the work of Christ a work of the sinner himself is necessary for salvation, there is doubt concerning Jesus the only Savior. The teaching denies that Jesus is a complete Savior and thus casts doubt on the truth that He is the only Savior. The immediate effect of the teaching is that those who believe it are doubtful about their salvation, since the teaching has convinced them that their salvation depends upon themselves. If this doubt about Jesus’ being the only Savior is not removed from the church by the condemnation of the heresy and by the deposition of the false teacher, if the doubt is tolerated, it will develop into doubt that Jesus is God incarnate and doubt that Scripture is God’s Word.

Certainty about One’s Own Salvation

Vitally important as these aspects of assurance are, they are not the subject of these editorials. The subject of these editorials is the certainty of the believing child of God of his own salvation personally. It is the certainty, not only that Jesus Christ is the Savior of sinners, but also that He is the Savior of me personally. It is the certainty, not only that the Bible is the inspired Word of God, but also that the Bible is the Word of God, as good news of grace and salvation in Christ, to me personally. It is the assurance of my own salvation.

The assurance of salvation is certainty that I am saved now. “These things have I written unto you that believe on the name of the Son of God; that ye may know that you have eternal life” (I John 5:13).

It is certainty that I will be saved everlastingly. To be sure of salvation today, but fearful that I may perish tomorrow and forever, is not certainty of salvation. Certainty of salvation includes that I am sure of persevering, according to the Word of the Savior to all His own, “My sheep hear my voice, and I know them, and they follow me: and I give unto them eternal life; and they shall never perish, neither shall any man pluck them out of my hand. My Father, which gave them me, is greater than all; and no man is able to pluck them out of my Father’s hand” (John 10:27-29)

Assurance of salvation is also certainty that I was saved from eternity past, in the decree of divine election. “Knowing, brethren beloved, your election of God” (I Thess. 1:4).

Included in the comfort of this rich and full assurance of salvation is certainty that my earthly life is so in the hand of my heavenly Father, and so precious to Him, that He will provide all things necessary and make all things work for my good. “I am sure,” exclaims every (Reformed) believer, child and adult, ” I have no doubt, but he [God my Father for Christ’s sake] will provide me with all things necessary for soul and body; and further, that He will make whatever evils He sends upon me, in this valley of tears, turn out to my advantage” (Heid. Cat., Q. 26).

The assurance of salvation is certainty, absolute certainty, as much as is one’s certainty that the Bible is the Word of God and that Jesus is the only Savior. It is absurd to speak of an “uncertain certainty.” An “uncertain certainty” is not assurance at all, but doubt.

Without the assurance of salvation, certainty about Christ as Savior and certainty about the Bible’s being the Word of God would be of no use to me. Positively, the assurance of salvation is closely related to assurance that the Bible is the Word of God and that the Christ revealed in the Bible is the only Savior. For the Bible promises that every one who knows and trusts in Jesus Christ alone for salvation is saved, has been saved from eternity, and will be saved everlastingly.

About the assurance of salvation, we have our questions.

Is this possible?

Is this possible for all believers?

Can we believers and children of believers be certain with absolute certainty?

How is this possible?

What about doubts in the experience of some believers?

What if I have doubts? even strong doubts?

The gospel as rightly understood and taught by the Reformed faith has answers to our questions.

Answers that do not encourage, nurture, and even breed doubt.

But answers that assure.