Rev. Key is pastor of the Protestant Reformed Church of Hull, Iowa.
As we proceed in our consideration of what has been called “The Golden Chain of Salvation,” we come to the activity of saving faith. We have seen that faith must first be understood as the bond by which God through the Holy Spirit grafts us into Christ. Nobody is saved without that bond, without being grafted into Christ. That includes infants. For all, the Bible teaches, are conceived and born in sin.
But in the doctrine of salvation, it is the activity of faith that is on the foreground. The living graft of salvation must of necessity come to expression in the conscious activity of the Christian.
Indeed, the call to conscious, active faith may well be called the keynote of the entire gospel. Among the last words that Jesus spoke to His disciples on this earth were these (Mark 16:15, 16): “Go ye into all the world, and preach the gospel to every creature. He that believeth and is baptized shall be saved; but he that believeth not shall be damned.” John writes in John 3:36, “He that believeth on the Son hath everlasting life: and he that believeth not the Son shall not see life; but the wrath of God abideth on him.” This truth runs through the Bible like an unbreakable thread. And therefore it is a matter of practical importance that we each personally consider the matter of the activity of faith, and see it in our own lives.
When it comes to the activity of saving faith, there are two elements that must be considered. The Heidelberg Catechism identifies them in Question and Answer 21 as “a certain knowledge” and “an assured confidence.” So true faith is defined—in its activity—as “not only a certain knowledge, whereby I hold for truth all that God has revealed to us in His Word, but also an assured confidence, which the Holy Spirit works by the gospel in my heart; that not only to others, but to me also, remission of sin, everlasting righteousness, and salvation are freely given by God, merely of grace, only for the sake of Christ’s merits.”
Both elements of saving faith, knowledge and confidence, come to expression in Paul’s confession, as we read in II Timothy 1:12b: “For I know whom I have believed, and am persuaded that he is able to keep that which I have committed unto him against that day.”
Intellectual Knowledge Is Insufficient
It should immediately be evident that a theoretical knowledge of God, a mere intellectual knowledge, is not sufficient for saving faith. Mere Bible knowledge (that which is sometimes called “historical faith”) is not to be identified with saving faith.
That is not to belittle intellectual knowledge. That is not to downplay the urgency of knowing sound doctrine. If you and I begin to neglect the study of God’s revelation, if we personally neglect the increase in knowledge of God’s Word and truth, it will not be long and we will hear very concretely the judgment of God as spoken in Hosea 4:6, “My people are destroyed for lack of knowledge: because thou hast rejected knowledge, I will also reject thee, that thou shalt be no priest to me: seeing thou hast forgotten the law of thy God, I will also forget thy children.”
Don’t minimize biblical, doctrinal knowledge! Don’t do that! The consequences are devastating! Many have departed from the truth, and have been lost in their generations because they ignored the necessity of knowing the truth of the Scriptures.
You cannot believe in the one only true God unless you know about Him. There must be more, of course. But intellectual knowledge you must have! Faith never separates itself from the Scriptures and the knowledge of the truth.
Nevertheless, mere intellectual knowledge is not sufficient to save us.
Spiritual, Experiential Knowledge Is Necessary
“And this is life eternal, that they might know thee the only true God, and Jesus Christ, whom thou hast sent” (John 17:3). The knowledge of faith is a heart knowledge. It is a personal, spiritual knowledge of intimacy and love.
In II Timothy 1:12, Paul says, “For I know whom I have believed.”
Have you ever been struck by the fact that the apostle does not even say whom he believed? You might say that Paul isn’t very specific here.
But Timothy immediately understood the reference, and so do we. The meaning of those words are familiar to all who have received the benefits of Christ by a true faith. They are heart words with all who have been taught by God and made wise unto salvation.
The One whom Paul knew and believed was the Christ of God.
The apostle had not always known Him. Even though Paul knew the Scriptures well, he had not always known Him who is the Subject of all God’s revelation in Scripture. In fact, Paul counted Christ an imposter! Anything spoken by Jesus of Nazareth was enough to prejudice Paul against it, and make him judge it as false doctrine. It wasn’t that Paul didn’t know intellectually the Old Testament testimony of the Messiah. But he did not know that Messiah with the spiritual knowledge of faith, until on the way to Damascus he “saw that Just One, and heard the voice of his mouth” speaking from the midst of heavenly glory, “Saul, Saul, why persecutest thou me?” And when Paul answered, “Who art thou, Lord,” the Lord said, “I am Jesus whom thou persecutest.” The man who was to become an apostle of our Lord could not believe until he heard those words.
The knowledge of faith is that knowledge that the Holy Spirit works in us by the power of the gospel. While a mere intellectual knowledge about Christ will never bring a sinner to his knees and will never bring life out of death, the knowledge of faith brings us into such a relationship with God through Christ that we cannot cling to our sins, but must confess them and flee from them. It is to know that we now live in an intimate union with Christ. Our life is in Him!
So our Heidelberg Catechism speaks in very personal language of “a certain knowledge whereby I hold for truth all that God has revealed to us in His Word.”
That knowledge the apostle John writes about in I John 5:19, 20, when he says, “And we know that we are of God, and the whole world lieth in wickedness. And we know that the Son of God is come, and hath given us an understanding, that we may know him that is true, and we are in him that is true, even in his Son Jesus Christ. This is the true God, and life eternal.”
A Fruitful Knowledge
Such certain knowledge of true faith can be known from the counterfeit, mere intellectual knowledge by its fruits.
The true and certain knowledge which is life eternal is a knowledge which fires up my affections toward God, sanctifies my will, and raises my mind to a level above that which I had known before.
It is a knowledge that produces in me love for God and for His Word, submission to Him, faith in Him.
It is such a knowledge that causes me to join Asaph inPsalm 73, as I proclaim from the depths of my soul: “Whom have I in heaven but thee: and there is none upon earth that I desire beside thee.” That is the knowledge of which Paul speaks to Timothy when he says, “I know whom I have believed.”
Do you see, then, how this knowledge differs from a mere intellectual knowledge?
The head knowledge which is all that many possess today, and that in very small measure, is a knowledge that has no influence upon their walk. It bears no fruit of practical godliness. It illustrates that horrible truth expressed by Jeremiah: “They proceed from evil to evil, and they know not me, saith the Lord” (Jeremiah 9:3). Jeremiah wasn’t speaking of what we might call the unchurched. He was speaking of the children of Israel, who had the law of God and His temple, who had the sacrifices and ceremonies pointing to their Messiah, who had God’s prophets proclaiming His gospel to them. They had been favored by God with so much; yet they were strangers to Him!
Whereas mere head knowledge does no more than fill one with pride and conceit, the knowledge of true faith brings us humbly to our knees before God, and moves us to seek the face of Christ our Savior.
Whereas the knowledge of the Pharisee caused him to pray, “God, I thank thee that I am not as other men are,” the knowledge of faith causes us to cry out, “God be merciful to me a sinner!”
While those who are the possessors of mere head knowledge may loudly sing the praises of God, that doesn’t change the fact that their home is the earth, and their longings the things of this world.
When you possess this knowledge of true faith, however, you look upon God as your Friend-Sovereign, and you long for His fellowship and glory. You know by experience what Paul meant when he wrote to the Philippian church, “I count all things but loss for the excellency of the knowledge of Christ Jesus my Lord” (Phil. 3:8).