It is relatively easy to learn facts. It is more difficult to apply them personally. It often takes considerable time for lessons to become embedded in our minds and be consistently reflected in our lives. John Owen was a man who excelled in personal application.

Commending in Public Only What He Experienced in Private

One great hindrance to holiness in the ministry of the Word is that we are prone to preach and write without pressing into the things we say and making them real to our own souls. Over the years words begin to come easy, and we find we can speak of mysteries without standing in awe; we can speak of purity without feeling pure; we can speak of zeal without spiritual passion; we can speak of God’s holiness without trembling; we can speak of sin without sorrow; we can speak of heaven without eagerness. And the result is an increasing hardening of the spiritual life.
   Words came easy for Owen, but he set himself against this terrible disease of inauthenticity and secured his growth in holiness. He began with the premise: “Our happiness consisteth not in the knowing the things of the gospel, but in the doing of them.” Doing, not just knowing, was the goal of all his studies.
   As a means to this authentic doing he labored to experience every truth he preached. He said,

I hold myself bound in conscience and in honor, not even to imagine that I have attained a proper knowledge of any one article of truth, mush less to publish it, unless through the Holy Spirit I have had such a taste of it, in its spiritual sense, that I may be able, from the heart, to say with the psalmist, “I have believed, and therefore I have spoken.”

So, for example, his Exposition of Psalm 130 (320 pages on eight verses) is the laying open not only of the Psalm but of his own heart. Andrew Thomason says,

When Owen . . . laid open the book of God, he laid open at the same time the book of his own heart and of his own history, and produced a book which . . . is rich in golden thoughts, and distinct with the living experience of “one who spake what he knew, and testified what he had seen.”

The same biographer said of Owen’s On The Grace and Duty of Being Spiritually Minded (1681) that he “first preached [it] to his own heart, and then to private congregation; and which reveals to us the almost untouched and untrodden eminences on which Own walked in the last years of his pilgrimage.”

—John Piper, Contending for Our All, 109-111