The Secret of Strength

The fortieth chapter of Isaiah is full of divine comfort, caution, and challenge. It breathes comfort as God tells his ancient people that the day of deliverance is as bright as his promises. He declares: “The glory of the LORD shall be revealed, and all flesh shall see it together: for the mouth of the LORD hath spoken it” (v. 5). It is a chapter of caution, for in the sentences that follow God warns his people to beware of likening the Creator of the universe to a graven image and a lifeless idol. The concluding paragraph, however, is supremely one of challenge, for it calls God’s people to renewed endeavors despite the weakness of the flesh and the wiles of the devil. The message of these final verses is that of the secret of strength.

To understand this secret, we must consider, first of all:

The Peril Of Expended Strength

“He giveth power to the faint; and to them that have no might he increaseth strength. Even the youths shall faint and be weary, and the young men shall utterly fall” (vv. 29, 30). In language familiar to us all, the prophet here outlines a perilous sequence. First there is a weariness that leads to weakness, and then a weakness that culminates in utter collapse. The words are intended to convey the danger of expended strength; and every one of us knows how alert the devil is to take advantage of this condition in our spiritual lives.

In Old Testament times Moses cautioned the children of Israel of this peril of expended strength. He warned: “Remember what Amalek did unto thee by the way.… how he … smote … all that were feeble behind thee, when thou wast faint and weary” (Deut. 25:17, 18). Then there is that instance when David found himself in deadly combat with one of the sons of the giants, and would have been slain but for the intervention of his faithful servant Abishai. The reason for David’s threatened defeat is that he had “waxed faint” (2 Sam. 21:15).

The Word of God and practical experience teach us that there are two ways in which spiritual strength can be expended. First of all, there are the demands of service. God has promised abundant strength to those who are prepared to appropriate it. But the very fact that he increases strength presupposes the expenditure of that strength in daily service.

The earthly life of our Lord Jesus illustrates this fact. When an ailing woman pressed through a thronging crowd to touch the hem of his garment and was healed of her disease, “Jesus, immediately knowing in himself that virtue had gone out of him, turned him about in the press, and said, Who touched my clothes?” (Mark 5:30). That word “virtue” can be translated “strength.” The release of healing power in that moment was, for Jesus, an expenditure of strength. And this was true of his teaching and preaching, as well as his healing ministry.

No one can exert an impact upon a godless world without expending strength. The demands of service take a toll on our resources.

But in the second place, there are the dissipations of sin. Perhaps the most sobering example of this expenditure of strength is sin in the life of Samson. Here was a man who was endowed with unusual powers, he has been known throughout the centuries as the Hercules of the Old Testament. But there came a moment in his experience when he tampered with sin and by doing so lost his strength, his sight, and his service for God.

One moment we can be in touch with the throne of God and living in glorious victory; then we can be utterly defeated through failure to draw upon the reserves of heaven. How we need to beware, then, of the peril of expended strength!

This leads us to another aspect:

The Principle Of Exchanged Strength

“They that wait upon the Lord shall renew their strength” (v. 31). The word chalaph—“renew”—can also be rendered “change” or “exchange.” Scholars suggest the word is associated with the process by which the molting eagle exchanges its old feathers for new ones, and so is fitted for its phenomenal flights.

Those who are familiar with the writings of J. Hudson Taylor will recall that he made much of what he calls “the exchanged life.” And Taylor was right, for this is the supreme fact of the Christian life—exchanging what we are for all that Christ is; it is the principle of normal Christian living. We begin the spiritual life that way and we continue and consummate it on the same basis.

The secret of this exchanged life is gathered up for us in that little word “wait”—“they that wait upon the Lord shall renew their strength.” As we study this word “wait” we see at least three conditions that bring us into the joy and fullness of the exchanged life. There is the waiting of dedication. This is the attitude not of rebellion but rather of submission. While there is rebellion in our hearts there is consequent impatience, restlessness, and frustration; but where there is submission to all the will of God there is restfulness before the Lord.

“When my agony of soul was at its height,” wrote Hudson Taylor,

a sentence in a letter … was used to remove the scales from my eyes, and the Spirit of God revealed the truth of our oneness with Jesus as I had never known it before. [The writer of the letter], who had been much exercised by the same sense of failure, but saw the light before I did, wrote … “But how to get faith strengthened? Not by striving after faith, but by resting on the Faithful One.” As I read I saw it all! “If we believe not, he abideth faithful.” I looked to Jesus and saw (and when I saw, oh, how the joy flowed!) that He had said, “I will never leave you.” “Ah, there is rest!” I thought. “I have striven in vain to rest in him. I’ll strive no more. For has he not promised to abide with me—never to leave me, never to fail me?” And, He never will! [“The Life of Rest,” Good News Publishers].

Paul brings this same thought out beautifully in his Epistle to the Philippians, where, having learned the secret of restfulness in the will of God, he declares, “I can do all things through Christ which strengtheneth me.” Do we know the waiting of dedication? Can we say with the psalmist, “I waited patiently for the LORD; and he inclined unto me, and heard my cry”?

There is also the waiting of supplication. Implicit in this word “wait” is the idea of supplication and prayerfulness. This, of course, is where the exchange is made. As we breathe our need to heaven, he answers with his help. As we confess our sin, he imparts his cleansing. As we admit our weakness, he infuses divine strength.

A glorious line in one of the psalms (96:6) puts this perfectly: “Strength and beauty are in his sanctuary.” If we are to know the exchange of strength and the transformation of our character into the likeness of the Lord Jesus Christ, then the secret is in the sanctuary. This is the place of prayer and supplication. Neglect the sanctuary and strength is gone. The sanctuary represents not only public worship but also private devotion. We must remember throughout our lives that “strength and beauty are in his sanctuary.”

There is, finally, the waiting of expectation. There is no point in waiting if there is no expectation. This is why James the Apostle says that when we come to God in prayer we should “ask in faith, nothing wavering: for he that wavereth is like a wave of the sea driven with the wind and tossed. For let not that man think that he shall receive anything of the Lord” (James 1:6, 7). On the other hand, to believe expectantly that God will meet our needs is to be rewarded with divine strength; the Bible says that “in quietness and in confidence shall be our strength.” The quietness of prayer and the confidence of expectation bring the answer of spiritual strength.

This, then, is the principle of exchanged strength. The strength of man is utter weakness, but when he exchanges it for divine strength the Christian becomes endued with power for any eventuality.

This brings us to the concluding point:

The Purpose Of Employed Strength

“They that wait upon the LORD shall renew their strength; they shall mount up with wings as eagles; they shall run, and not be weary; and they shall walk, and not faint” (v. 31). With striking imagery we are here introduced to the exciting and exhilarating adventures we can have with God. Some have suggested that the language describes the three stages of Christian development: mounting up with wings as eagles represents children; running and not being weary represents young men; and walking and not fainting represents fathers.

As impressive as this is, I am inclined to interpret the passage differently. I believe that the purpose for which God releases divine strength is to prepare us for three areas of Christian experience. First, there is the area of life’s special exaltations—“they shall mount up with wings as eagles.” W. E. Vine in his commentary on Isaiah points out that “the eagle is characterized by three things: rapidity of flight, power of scent, and keenness of vision.” And then he adds: “So our mounting up is not only a matter of rising above difficulties, but involves a joyous and quick discernment of the will of God for us, and the keen vision of Himself by faith” (Isaiah, 1946, p. 98).

The eagle is the only bird that can fly into the eye of the sun. It has a special lid that protects the retina from the dazzling brightness and unrelenting heat of the sun. This is why the Gospel of John is likened to the eagle: there the Apostle flies into the very eye of the sun and reveals truths of transcendent wonder and beauty. We need special strength for these exalted experiences of life.

Paul gives testimony to this fact when he tells us that his prayer for the Ephesian Christians was that God would strengthen them by his might in the inner man, that Christ might dwell in their hearts by faith (Eph. 3:16, 17). There is nothing more wonderful in all the world than the glory of the indwelling Christ. To enter into the full experience of the Saviour’s indwelling, to know the depth, height, length, and breadth of divine love, we must be strengthened with might by God’s Spirit in the inner man. Perhaps one of the reasons why we do not enjoy these exaltations of life more often is because we do not take time to wait upon the Lord for the needed strength.

Then, secondly, there is the area of life’s crucial obligations—“they shall run, and not be weary.” We cannot afford to play at church or to procrastinate in soul-winning. The messenger of the Good News must have winged feet. I love the story of Philip the evangelist, who was called out of a revival in the city of Samaria and told to join himself to the carriage of the Ethiopian eunuch, returning to his homeland in North Africa. Perhaps Philip hesitated somewhat when he first saw this black man sitting in his chariot and reading Isaiah the prophet. But then came the word of the Spirit unto him, saying, “Go near, and join thyself to this chariot.” And we read that “Philip ran … to him” (Acts 8:30).

The crucial obligations of every true Christian are those of carrying the Gospel to the far ends of the earth. The task is to be done as quickly as possible. For this we need special strength to run and not be weary. We cannot loiter or be lazy in fulfilling the King’s business. For such demands as this we need the exchanged life with its divine strength.

With the exaltations of life and the obligations of life there is, thirdly, the area of life’s normal activities—“they shall walk, and not faint” (v. 31). “The daily round and common task,” our everyday duties and hobbies and pastimes, call for a steady plodding every moment of every hour. I believe this is why the Christian life, in its totality, is described as “a walk.” Seven times over in the Epistle of Paul to the Ephesians we are told how to walk; and strange as it may seem, this is the area in which we are most likely to faint. We all want special exaltations, and if our dedication to God is true we want to be involved in crucial obligations. But when it comes to the normal activities, we tend to rely on our own strength, and when we do this we collapse. The text we are studying underscores the truth that appears again and again throughout the Word of God: that in and of ourselves we cannot please God. Whether we are flying, running, or walking, we need the strength of God. Failure to recognize this is the cause of spiritual bankruptcy and moral breakdown in the Church of Jesus Christ today.

We need to heed Isaiah’s message on the secret of strength. We need to remember the peril of expended strength; then we can enter into the joy and purpose of employed strength. God is saying to us, “They that wait upon the Lord shall exchange their strength”—for his.

Stephen F. Olford has served as pastor of Calvary Baptist Church in New York City since 1959. He was born in Zambia of missionary parents and studied in England at St. Luke’s College and the Missionary Training Colony.

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