John Dagg’s Manual of the Theology begins with a brief section called “The Obligation.” Here, Dagg lays out why we should study theology and what we should expect from it. To borrow another pastor-theologian’s language, studying theology should be a transformative ‘duty of delight’:
The study of religious truth ought to be undertaken and prosecuted from a sense of duty, and with a view to the improvement of the heart. When learned, it ought not to be laid on the shelf, as an object of speculation; but it should be deposited deep in the heart, where its sanctifying power ought to be felt. To study theology, for the purpose of gratifying curiosity, or preparing for a profession, is an abuse and profanation of what ought to be regarded as most holy. To learn things pertaining to God, merely for the sake of amusement, or secular advantage, or to gratify the mere love of knowledge, is to treat the Most High with contempt. . . .
It is a peculiar glory and excellence of the Christian revelation, that it is adapted to this fallen condition of mankind; and that it has power to effect a restoration. It is medicine for the sick, as well as food for the healthy. A healthy appetite calls for food; and the food, when received, administers needed nourishment; so that between the healthy stomach and the nutritious food, the adaptation is reciprocal. But in sickness the stomach loathes food, and rejects the medicine which is needed to effect a cure: yet the adaptation of the medicine to the condition of the sick man still remains. Just so it is with respect to the gospel of Christ. Though rejected by men, it is “worthy of all acceptation,” because it is a remedy, precisely adapted to our depraved state. Thousands of thousands have experienced its restoring power, and unite in recommending its efficacy to the multitudes who are unwilling to make trial of it.
In contemplating the truths of religion, we may view them in various aspects. We may consider them as proceeding from God; as demonstrated by abundant proof; as harmonizing with one another; and as tending to the glory of God. It is interesting and instructive to view them in immediate contact with the human heart, and, like the Spirit of God, brooding over the original chaos, bringing order out of confusion, and infusing light and life where darkness and death had previously reigned. In exerting this new-creating power, the divinity of Christian truth appears; and the demonstration of it is the more satisfactory, because practical, and leveled to the capacity of all.
As religious beings, let us seek to understand the truths of religion. As immortal beings, let us strive to make ourselves acquainted with the doctrine on which our everlasting happiness depends. And let us be careful that we do not merely receive it coldly into our understanding, but that its renewing power is ever operative in our hearts.