In Christless Christianity, we read the following helping us understand why Dr. Horton...
says the above principle must be followed:
I recently heard a sermon that ended with the appeal, ‘Are you going to accomplish great things for God?’ It is easy for believers with a sensitive conscience to come away from the average spiritual diet in church thinking they must be a Paul in evangelism, a Wilberforce in culture, and a Thomas a Kempis in spiritual disciplines. Radical discipleship in this triumphalistic vein seems rather far from Jesus’ invitation, ‘Come to me, all who labor and are heavy laden, and I will give you rest. Take my yoke upon you, and learn from me, for I am gentle and lowly in heart, and you will find rest for your souls. For my yoke is easy and my burden is light’ (Matt. 11:28-30).Read through chapters 11 and 12 in the book of Hebrews and ask yourself whether Horton’s vision of the life of faith captures what is portrayed there? After the chronicle of lives lived by faith producing extraordinary works in chapter 11, we're told these men and women are witnesses to us—examples of faithful living.
Calling us to accomplish great things for God is part of the hype that constantly burns out millions of professing Christians. Telling us about the great things God has accomplished—and more than that, actually delivering his achievement to sinners—is the real mission of the church. And it might even put wind in the sails of those among us whom God has called to extraordinary achievements! But it will be enough if it puts wind in the sails of those whom God has called to ordinary and fruitful lives. On Monday, a congregation once again assured of God’s amazing grace to sinners, will be scattered into the world as salt and light. If we think the main mission of the church is to improve life in Adam and add a little moral strength to this fading evil age, we have not yet understood the radical condition for which Christ is such a radical solution (Christless Christianity, 210-211).
Why are comfortable Americans being burned out by being called “to accomplish great things for God,” while the recipients of Hebrews who were being threatened with the loss of all their earthly goods and their very lives are exhorted to lay aside every encumbrance and sin, to run with endurance, and to resist sin to the point of shedding blood? If only verse 12, where we're told to fix our eyes on Jesus, the Author and Perfecter of faith, wasn’t confused by the exhortation of verse 11.
(1) Therefore, since we have so great a cloud of witnesses surrounding us, let us also lay aside every encumbrance and the sin which so easily entangles us, and let us run with endurance the race that is set before us,(2) fixing our eyes on Jesus, the author and perfecter of faith, who for the joy set before Him endured the cross, despising the shame, and has sat down at the right hand of the throne of God.
Dr. Horton and others in his camp are always dogging pietists. If one believes calling people “to accomplish great things for God” leads to burnout, you'll not only shy away from calling people to rescue babies from the hands of murderers, but you'll avoid calling people to actual holiness. The calling to walk in a manner worthy of Jesus Christ, to please him in all respects (Col. 1:10), is to accomplishment great things for God.
The exhortation to the young man struggling with depression or lust or anger or lying or cowardice will be “fix your eyes on Jesus” without what precedes: “lay aside every encumbrance and the sin which so easily entangles us.” The exhortation will be to coast steadily through the race rather than “run with endurance.” And not only his own life, but the Church, too, will be worse off for a man making peace with his sins.
Calvin's great accomplishment wasn't simply his publication of the Institutes. It was also his constant battle and overcoming of his sin of timidity (see the preface of his commentary on the Psalms).
Had William Farel shared the position of Dr. Horton, Calvin would have received a nice massage rather than the imprecations that led him to fear God and get to work shepherding Geneva.