Spiritual truths differ from natural truths both in their constitution and in the manner of their apprehension by us.
Natural truths can be learned by us regardless of our moral or spiritual condition. The truths of the natural sciences, for instance, can be grasped by anyone of normal intelligence regardless of whether he is a good man or a scoundrel. There is no relation between, say, chastity and logic, or between kindness and oceanography. In like manner a sufficient degree of mental vigor is all that is required to grasp philosophical propositions. A man may study philosophy for a lifetime, teach it, write books about it, and be all the while proud, covetous and thoroughly dishonest in his private dealings.
The same thing may be said of theology. A man need not be godly to learn theology. Indeed I wonder whether there is anything taught in any seminary on earth that could not be learned by a brigand or a swindler as well as by a consecrated Christian. While I have no doubt that the majority of theological students live far better than average lives, yet it should be kept in mind that they can easily get their lessons without living any better than is absolutely required to stay in the institution.
It does not strain my imagination to think of Judas Iscariot as coming out of school with a Th.B., if such a thing had been offered in his day. There is simply no necessary relation between the studies engaged in by students in a divinity school and the state of the students' hearts.
Anything that is taught under the heading of hamartiology, Soteriology, eschatology, pneumatology or any of the rest may be grasped as easily by a sinner as by a saint. And certainly it takes no great degree of sanctity to learn Hebrew and Greek.
Surely God has that to say to the pure in heart which He cannot say to the man of sinful life. But what He has to say is not theological, it is spiritual; and right there lies the weight of my argument. Spiritual truths cannot be received in the ordinary way of nature. "The natural man receiveth not the things of the Spirit of God: for they are foolishness unto him: neither can he know them, because they are spiritually discerned." So wrote the apostle Paul to the believers at Corinth.
Our Lord referred to this kind of Spirit-enlightened knowledge many times. To Him it was the fruit of a divine illumination, not contrary to but altogether beyond mere intellectual light.
The fourth Gospel is full of this idea; indeed the idea is so important to the understanding of John's Gospel that anyone who denies it might as well give up trying to grasp our Lord's teachings as given by the apostle John. And the same idea is found in John's First Epistle, making that epistle extremely difficult to understand but also making it one of the most beautiful and rewarding of all the epistles of the New Testament when its teachings are spiritually discerned.
The necessity for spiritual illumination before we can grasp spiritual truths is taught throughout the entire New Testament and is altogether in accord with the teachings of the Psalms, the Proverbs and the Prophets. The Old Testament Apocrypha agrees with the Scriptures here, and while the Apocryphal books are not to be received as divinely inspired, they are useful as showing how the best minds of ancient Israel thought about this matter of divine truth and how it is received into the human heart.
The New Testament draws a sharp line between the natural mind and the mind that has been touched by divine fire. When Peter made his good confession, "Thou art the Christ, the Son of the living God," our Lord replied, "Blessed art thou, Simon Bar-jona: for flesh and blood hath not revealed it unto thee, but my Father which is in heaven." And Paul expresses much the same thing when he says, "No man can say that Jesus is the Lord, but by the Holy Ghost."
The sum of what I am saying is that there is an illumination, divinely bestowed, without which theological truth is information and nothing more. While this illumination is never given apart from theology, it is entirely possible to have theology without the illumination. This results in what has been called "dead orthodoxy," and while there may be some who deny that it is possible to be both orthodox and dead at the same time I am afraid experience proves that it is.
Revivals, as they have appeared at various times among the churches of the past, have been essentially a quickening of the spiritual life of persons already orthodox. The revivalist, as long as he exercised his ministry as a revivalist, did not try to teach doctrine. His one object was to bring about a quickening of the churches which while orthodox in creed were devoid of spiritual life. When he went beyond this he was something else than a revivalist. Revival can come only to those who know truth. When the inner meaning of familiar doctrines suddenly flashes in upon the heart of a Christian the revival for him has already begun. It may go on to be much more than this but it can never be less.